A Strategy for Planned Product Aging in View of Sustainable Development Challenges

Abstract

In this paper, the issue of the deliberate aging of products by manufacturers is discussed. Deliberate aging consists in intentionally planning or designing a product with an artificially limited lifetime in order to force consumers to replace it faster. The resulting rapid acceleration of the cycle of obtaining and utilizing consumer goods has serious consequences in the form of negative externalities. For this reason, the conscious aging of products is now recognized as the cause of unjustified consumption, generating huge economic and social costs and leading to the devastation of the natural environment and excessive exploitation of natural resources. Thus, it is in clear contradiction to the model of sustainable development. The aim of this paper was to identify the purchasing attitudes of buyers in the durable goods market. For its implementation, a pilot questionnaire study, which covered a representative group of 354 respondents, was carried out. The results indicate that the factors that influence the purchase of restitution goods depend on the type of product and the consumer’s income. At the same time, about two thirds of the respondents recognized the problem of the deliberate aging of products. In their opinion, the goods produced in the autarkic economy were more durable and their life cycle was much longer. The results obtained require further empirical verification carried out in comparative studies.

1. Introduction

In the third decade of the 21st century, the circular economy has gained importance as an extension of the sustainable development concept by taking into account environmental protection and providing useful business solutions [1,2,3]. In this respect, product and process innovation has been identified as a key factor for growth and environmental sustainability [4]. An important role in the implementation of the sustainable and balanced growth assumptions is played by the value for the consumer and self-identity, which have gained a leading role in theory and practice [5,6]. Identity can be defined as the way an individual perceives himself or herself and how they decide to follow the values and behavior of the group of people with whom they want to be or feel connected [7]. In this context, identity can be defined as a key component of assessing the preferences and value-building process of an individual [8,9]. In the area of environmental or “green” issues, due to their growing importance and specificity, there is a general agreement among researchers that self-identity takes the form and name of “green identity” [7,10,11,12], referring to a “consumer’s overall assessment of the product or service net benefit, between what is received and what is provided, based on the consumer’s environmental wishes, balanced expectations and green needs” [11]. These research findings suggest that the perceived value of green products may be influenced by the consumer’s value system—in particular, the degree to which the consumer identifies as an environmentally responsible person. At the same time, producers frequently use controversial practices that undermine the idea of sustainable development and reduce quality, and thus also consumer welfare. One of such activities is the phenomenon of planned obsolescence [13].

The strategy of the planned aging of products is an element of well-thought-out business activities [14,15], which leads to a decrease in their usefulness against economic [16], social and environmental premises [17]. The resulting rapid acceleration of the cycle of obtaining and utilizing consumer goods has serious consequences in the form of negative externalities [18]. Whether it is the accumulation of waste and pollution, greenhouse gas emissions, water eutrophication, destruction of the ozone layer or depletion of natural resources, all of these lead to ecological imbalance [19,20]. Undoubtedly, the planned aging of products contributes to the waste of natural resources and the degradation of the natural environment as a whole. This is the result of: (1) the use of new resources and energy to produce new goods; (2) sending an increasing amount of products to landfill; and (3) the use of new energy in the case of recycling.

In the case of planned aging, the usefulness of products is shortened against economic, social and environmental rationale. The resulting rapid acceleration of the cycle of obtaining and utilizing consumer goods has serious consequences in the form of negative externalities. The accumulation of waste and pollution, emission of greenhouse gases, water eutrophication, destruction of the ozone layer and depletion of natural resources lead to disturbances in the ecological balance. On the other hand, the continuous, artificially provoked exchange of products as an alternative to their repair increases household expenses, promotes consumerism by creating a dissonance between the real needs and the possibilities of the buyer [21] and eliminates jobs in the repair industry [21,22]. Thus, even if the argument that planned obsolescence helps save limited resources per unit produced (through the use of cheaper components or the use of technological progress) is accepted [23], it is impossible to ignore the fact that, on the whole, it leads to an increase in total production by reducing costs and lowering prices, stimulating a further demand growth [24]. It is worth noting that the issue of responsibility for the negative effects of planned product aging does not rest only with the producers. Perceiving the buyer only as a victim of a well-thought-out business strategy is definitely short sighted due to the fact that the decision to exchange a good is complex [24] and depends on the subjective assessment of the consumer [20,25,26,27,28,29]. For this reason, the problem of planned obsolescence has attracted the attention of many stakeholders, including the media, community and consumer protection organizations, academics, businesses and institutions, and has been the subject of wide public debate at local and international levels [30]. One of its effects is the gradual introduction of institutional solutions aimed at combating the abuses arising in this area and improving the effectiveness of their prosecution by law [31].

The aim of this paper was to identify the purchasing attitudes of buyers in the durable goods market. The authors wanted to assess whether the experiences of using household goods are positive or negative from the point of view of durability, functionality and usability. It was assumed that, due to the costs of restitution purchases and environmental protection, customers were guided not so much by the price of the product, but by the functionality and durability of the goods.

2. Literature Review

Planned aging of products, combined with the reluctance of individuals to postpone consumption in time, is now recognized as the cause of the development of consumerism which consists in the purchase of goods unjustified by real human needs, without taking into account social, environmental and individual costs [32]. It is the result of taking advantage of the emotional character of buyers’ behavior by producers [32,33]. The emergence of consumerism coincided with the concept of “consumer society” promoted by advertisers in the 1920s and stimulated by the development of consumer credit. Consumers consistently had a new lifestyle imposed on them which focused on material values and a rapid increase in the standard of living [34]. Since then, the phenomenon of product aging developed in two directions. First, producers started to produce lower-quality products [35]. Secondly, companies tried to stimulate consumption using psychological mechanisms, encouraging buyers to get rid of products against functional and economic reasons for their further use [36]. With the passage of time, the growing awareness of the negative consequences of consumerism [37] and the progressive degradation of the natural environment meant that the problem of the planned aging of products began to be raised in a new context—excessive, unjustified exploitation of resources. Thus, it became one of the fundamental issues in the concept of sustainable development, whose important elements are sustainable consumption and production [38]. The change in consumer attitudes is confirmed by Eurobarometer surveys of June 2014. Their results show that 77% of EU consumers declared that they would rather repair damaged goods than buy new ones. They would also like to have easy access to unambiguous information on the durability of the products purchased and the possibility of their repair [23]. Meanwhile, according to a report published by the European Parliament, the average lifetime of products is progressively shortening. In the case of smartphones, toys and shoes, it is 1–2 years, computers and outerwear 3–4 years, vacuum cleaners and dishwashers 5–6 years and cars and refrigerators 7–10 years [23,25]. Today’s household items are durable from 2 to 12 years, although they are made of materials that should remain usable for at least half a century—meaning 99% of the products will become obsolete over time, which will cost people from EUR 40,000 to 50,000 over the course of their lifetime [25]. For this reason, although the strategy of the planned aging of products is generally not prohibited by law, and manufacturers are free to determine the level of durability of their products [38], it is increasingly postulated that it should be regulated as a separate area of anti-consumer practices [39,40]. However, the situation is complicated by the fact that unambiguous identification of planned aging cases is extremely difficult and is based more on suspicions than on real examples [39,41]. An additional complication in the process of proving planned obsolescence is that corporate strategies are protected by industrial secrecy. Moreover, by 2015, no legal tools useful for tracking fraud had been developed, and attempts to use the method of comparing the viability of objects over time were not sufficiently reliable [23,42].

The year 2015 turned out to be a breakthrough. It was then that the French Parliament took a decisive action to combat the planned aging of products, which, as part of the larger movement against the planned aging of products in the European Union, introduced an obligation to declare the expected life of products and inform consumers about how long spare parts for them will be manufactured. In the same year, the French Assemblée Nationale imposed a fine of EUR 300,000 and a prison sentence of up to two years on manufacturers planning to fail their products in advance [43]. On the other hand, in 2016, a law was introduced according to which manufacturers are obliged to repair or replace a defective product free of charge under warranty within two years from the date of original purchase [44]. Thus, France not only became the leader in the application of sanctions against abuses related to the deliberate aging of products, but also the first country where the concept of planned obsolescence was defined for the purposes of law, assuming that it consists in the deliberate introduction of a defect, a planned stoppage, technical limitations, incompatibilities or other obstacles to repair [45]. Similar solutions of a national nature are also currently being introduced by other countries. For instance, the Spanish Foundation for Energy and Sustainable Innovation Without Planned Obsolescence grants companies a special ISSOP label confirming that they produce environmentally friendly goods and services without planned obsolescence, thus contributing to the reduction in emissions and the proper management of waste [46]. In Sweden, on the other hand, special tax breaks for the repair of used goods, including electronic equipment and clothes, have been introduced; e.g., VAT has been reduced from 25% to 12% when repairing bicycles, while the cost of repairing audio and video equipment and household appliances is tax deductible [47]. Even before the solutions adopted by France, in 2013, the European Economic and Social Committee announced that it was considering a total ban on the planned aging of products. The crowning argument was that replacing products that are supposed to stop working within two or three years of their purchase is an obvious waste of energy and resources and a way of generating unnecessary pollution [48,49,50]. The “Best Practices for Built-in Aging and Shared Consumption”, convened in Madrid one year later, called for sustainable consumption to be recognized as a consumer right in EU legislation [50]. The postulate to introduce a labeling system indicating the durability of the product would give consumers the right to decide whether they prefer to buy a cheap product or a more expensive but more durable one [49]. On 4 July 2017, the “Resolution of the European Parliament on a longer life cycle of products: benefits for consumers and businesses” was adopted. It emphasizes that at all stages of the life cycle of products, a balance must be found between extending the life cycle of products, turning waste into secondary raw materials, industrial symbiosis, innovation [51], consumer demand, environmental protection and growth policy. At the same time, the development of increasingly resource-efficient products must not encourage shortening the life cycle of products or their premature disposal. On the other hand, elements such as product durability, extended warranty, availability of spare parts, ease of repair and exchangeability of components should be included in the manufacturer’s commercial offer and meet the diverse needs, expectations and preferences of consumers.

As a result of the legislative measures taken, the EU member states, under Directive 1999/44/EC of the European Parliament and of the Council of 25 May 1999 on certain aspects of the sale of consumer goods and related guarantees, introduced provisions granting consumers a longer warranty protection [52]. On the other hand, from April 2021, regulations governing the lifetime of consumer products intended for households, such as computers, televisions, refrigerators, washing machines and dishwashers, came into force. In the future, it is planned to create a system to detect planned aging of products and to reorganize production to make it more sustainable. New products are to be durable, designed for energy efficiency, maintained and updated, and made of recycled materials. According to the Vice President of the European Commission for Jobs, Growth, Investments and Competitiveness J. Katainen, the following can be saved by European households: an average of EUR 150 per year, a reduction of over 46 million tons of CO₂ equivalent and energy savings equal to the annual energy consumption in Denmark by 2030 [53]. Although the problem of the planned aging of products has been present in economic considerations for a long time, the research undertaken in this area is fragmentary and focuses primarily on its supply side. It relates to a small material scope [54], a selected, narrow group of respondents [55] and a specific market structure [56] and is of the nature of regional analyses [57] without the possibility of universal scaling. Rare attempts to model the process mainly concern the high technology industry [58]. In the Polish literature on the subject, this problem is actually only taken up by Ryś from the perspective of consumer identification [59]. Bearing in mind the literature review and the measures cited in the fight against the planned aging of products, it is important to monitor the level of consumer awareness of environmental responsibility and consumer sensitivity to environmental issues, and the subject of sustainable development in the context of the strategy and promotion of an economy based on the reuse and repair of products.

3. Materials and Methods

3.1. Research Material

In the period from November 2020 to January 2021, a pilot study, whose purpose was to check the correctness of the assumed research procedure, the selection of respondents, the adopted variable indicators or the research tools used, was carried out. This was particularly important because the planned main study will be extensive (costly and time consuming). The preliminary examination conducted was to be a source of introductory information on the correctness of the adopted research procedure. In connection with the above, the source of empirical data in the analysis was a random sample of 384 respondents—Polish residents aged 19 and older, who were owners or users of durable products that were in their possession for at least 2 years. The main purpose of the questionnaire study was to determine:

[1]

To what extent respondents noticed signs of planned aging of products by producers so that customers would buy durable goods more often;

[2]

Whether the perception of this phenomenon depended on the identified attitudes of respondents (buyers of durable goods), especially towards the life expectancy of selected durable products.

In particular, an attempt was made to identify the main determinants of the perception of product aging by producers and distinguish respondent profiles in terms of attitudes towards preferences/criteria when purchasing durable goods, and noticing signs of planned aging of products. Therefore, the pilot survey questionnaire consisted of 2 parts: the first was devoted to customer purchasing decisions in the context of product life expectancy; the second was devoted to purchasing determinants of durable goods in a household. It included 20 questions, appropriately grouped thematically in terms of the period of functioning/use of selected products by respondents, self-assessment of the products used (in terms of quality of workmanship, esthetics, ease of use, energy efficiency), self-assessment of product brands in terms of durability, the importance of the lifespan of durable products, the main determinants of the purchase of selected products and opinions on the deliberate aging of products by producers. In addition to general questions, the questionnaire contained specific questions for selected durable products, such as: a washing machine, a refrigerator, a cooker, an electric kettle, a dishwasher, a vacuum cleaner, a computer, a mobile phone, a car and a bicycle. In the questionnaire, both closed and semi-open, single- or multiple-choice questions were used.

The survey was conducted through an electronic form, on an internet web platform. Participation in the study was anonymous.

3.2. Methodology Research

The analysis assumed that the explained (dependent) variable was the perception of the phenomenon of the deliberate aging of products by producers so that customers would buy durable goods more often (Y). This variable was assigned a Likert value scale depending on the respondent’s answer to whether they agreed with the above statement:

• Definitely not;
• Probably not;
• It’s hard to say
• Rather yes;
• Definitely yes.

On the other hand, the group of independent variables was selected based on the questions included in the questionnaire concerning the following:

-

Purchase of any durable product within the last two years (variable X₁ of the values 1—yes, 0—no);

-

The main determinant of purchases of durable goods (X₂ variable concerning price, appearance, functionality, durability, innovation, quality, with values 1—yes, 0—no, for 10 individual products such as: a washing machine, a refrigerator, a cooker, an electric kettle, a dishwasher, a vacuum cleaner, a computer, a mobile phone, a car, a bicycle);

-

Self-assessment of the importance of the life expectancy/functioning of the possessed durable products (X₃ variable with a scale of values: 1—very small; 2—small; 3—neither large nor small; 4—large; 5—very large);

-

Self-assessment of the duration of operation of the equipment used in comparison to the assumed time on the day of purchase (X₄ variable with a scale of values: 1—definitely shorter; 2—neither longer nor shorter; 3—rather longer; 4—definitely longer);

-

Self-assessment of used products in the household in terms of: quality of workmanship, esthetics, ease of use, energy efficiency (the X₅ variable relating to quality, esthetics, ease of use, energy efficiency, with values 1—very low level, 2—poor, 3—satisfactory, 4—good, 5—very good, for each product, such as a washing machine, a fridge, a cooker, an electric kettle, a dishwasher, a vacuum cleaner, a computer, a mobile phone, a car, a bicycle);

-

Dealing with the breakdown of a product after the warranty period: buying a new one and throwing away the broken product, buying a new one and storing the broken product at home, repairing broken hardware and carrying product’s use on (X₆ variable for these three situations: a new one–broken out, new one–broken at home, no new one–repair broken one, each with values 1– yes, 0—no);

-

Belief in the correctness of the phrase: “many products available in the market are of lower quality than the products manufactured before the political transformation in Poland, i.e., before 1990” (variable X₇ with values 1—definitely not; 2—probably not; 3—hard to say; 4—rather yes; 5—definitely yes);

-

Belief in the correctness of the phrase: “products made in Asia are less durable than those made in Poland” (variable X₈ with values 1—definitely not; 2—rather not; 3—it’s hard to say; 4—rather yes; 5—definitely yes).

On the other hand, the control variables were as follows:

-

Respondent’s gender (X₉; W—female, M—male);

-

Age group (X₁₀; 19–29; 30–49; 50–69; 70 years and more);

-

Education (X₁₁; 1—elementary completed, no education; 2—lower secondary; 3—basic vocational; 4—post-secondary, secondary vocational and general education; 5—higher);

-

Net income per person in the household (X₁₂; up to PLN 2000; PLN 2001—4000; PLN 4001—6000; PLN 6001 and more);

-

Place of residence (X₁₃; 4—cities with more than 100,000 inhabitants; 3—cities with up to 100,000 inhabitants).

The first stage included the analysis of the independence of the dependent variable and the independent variables adopted.

To verify whether the two selected classification criteria of the group of respondents (pairs of variables: Y and one of the variables X₁ or X₁₂, which are qualitative in nature) are independent at the adopted significance level of α = 0.05, appropriate multi-way tables were constructed, and the Pearson chi-square test of independence was used. In a situation where the size of the multi-way table was below 10, the chi-square and NW (maximum likelihood) tests were used [60]. The decision to reject/accept the null hypothesis was based on the probability p (p-value) determined for the established value of the empirical test statistic χ². If the p-value was less than or equal to the adopted significance level α = 0.05, then the null hypothesis concerning the independence of X and Y was rejected in favor of the alternative hypothesis concerning the dependence of X and Y.

For this purpose, an algorithm for building classification trees, one of the data mining methods, was applied. The second stage of the analysis included an attempt to identify the main causes related to the phenomenon of the deliberate aging of products and, consequently, to distinguish relatively homogeneous classes of respondents taking into account the criteria resulting from the study (attitudes and behavior of users of durable goods). Its use in discriminant and regression analysis was initiated by Breiman et al. [60]. Currently, this method is increasingly used in many different research fields, not only in the field of statistics and econometrics but also in medicine, e.g., in determining survival predictions [61,62]. The use of classification trees in strategies of segmentation of individuals, e.g., recipients of health services, for which appropriate segmentation into homogeneous subgroups may constitute a basis for targeted interventions by the health service [63,64], or to identify significant food choices that affect health and define respondent profiles in terms of food choices [65], is of great interest. This wide use of classification trees is primarily related to the simplicity of the interpretation of results. This simplicity is valuable mainly because of the simple “model” that explains why observations are classified or predicted the way they are. In this type of analysis, classification tree methods can disclose relationships between several variables that would not be detected by other analytical techniques. Therefore, in the study presented, the classification tree algorithm was used to analyze the relationship of each explanatory variable (X_i, i = 1, …, 12) with the dependent variable (Y) and to determine whether the respondents belonged to disjoint segments, or qualitative classes of the dependent variable (Y, perceiving the deliberate aging of products by producers) on the basis of measurements of explanatory variables (X_i, i = 1, …, 12, i.e., selected attitudes and behaviors of buyers of durable goods).

Due to the qualitative and categorical nature of the dependent variable Y and the goal of classifying, the analysis was based on classification and regression trees. Unlike other statistical methods, classification trees do not require any preliminary assumption as to the nature of the relationship between the predictors and the dependent variable. Moreover, these methods are well suited to data mining tasks, where there is often little a priori knowledge, and there are no sound theories or assessments of what variables are related and how. This was a premise for the use of classification trees, and the variables that were selected for the model during the construction of the classification tree and that determined the subsequent divisions of the surveyed population of respondents (in the appropriate nodes of the tree) and profiled the relevant subsets of the surveyed population were, at the same time, the variables that determined the perception of signs of planned aging of products by manufacturers. The final division of the population studied is illustrated by the end nodes—the lists containing information on: the number of respondents assigned to individual classes and histograms of the frequency distribution of the dependent variable. In order to obtain a relatively simple classification tree, it was necessary to stop the procedure of recursive group division before achieving full homogeneity of segments and classes. For this purpose, the FACT (Fast Algorithm for Classification Trees) direct stop rule was used for a given fraction of objects—5% of the studied population.

The pilot nature of the study naturally resulted in a smaller sample size than in the target study; moreover, the limited duration of the study resulted in no response, which, ultimately, was the reason for the use of the simplified dependent variable. It turned out to be necessary to recode the five-valued original variable Y into a binary form.

The value of 1 that defines agreement with the opinion that producers deliberately age products so that customers buy durable goods more often was assigned by combining answers to one category (“rather yes” and “definitely yes”). On the other hand, possible responses to the primary variable in two variants: “probably not” and “hard to say’ (no answer was recorded as “definitely no” in the pilot study), were assigned the value of 0.

Of course, such a simplification results in a loss of information, but due to the pilot nature of the study, the use of the simplified model is sufficient since it allows indicating the variables that, during the tree construction, had the greatest classification power, dividing significantly different respondents into classes. On this basis, despite the adopted simplification, it can be assumed that these are the variables that determine the respondents’ attitude towards the opinion on aging products. In this sense, the simplified model can be used to test the analytical method, which in the target study will be based on the original dependent variable.

In addition, in order to avoid excessive detail in the analysis of all 10 products included in the study (such as: washing machine, refrigerator, stove, electric kettle, dishwasher, vacuum cleaner and computer, mobile phone, also a car, a bicycle) for each of the main determinants of the purchase of durable goods an auxiliary synthetic variable was constructed. The synthetic variable was the sum of the values of the variables recorded for individual 10 products (frequency of indicating a particular determinant).Thus, the synthetic variable X₂ for each main purchasing determinant has the form

$$X_2^{synthetic}={\sum }_{i=1}^{10}{X}_{2\left(D\right)}^i,$$

(1)

where:

i—a product (1—a washing machine, 2—a fridge, 3—a cooker, 4—an electric kettle, 5—a dishwasher, 6—a vacuum cleaner, 7—a computer, 8—a mobile phone, 9—a car, 10—a bicycle);

D—Determinant that stands for price, appearance, functionality, durability, brand, innovativeness and quality. For each purchasing determinant, the X₂ variable may take values from 0 (when purchasing any product, the respondent did not use a given determinant) to 10 (when purchasing each of the aforementioned products, the respondent used the same determinant).

Similarly, in the case of the self-assessment of individual products used in the household in terms of: quality of workmanship, esthetics, ease of use and energy efficiency, an auxiliary synthetic variable was constructed as the average of the values recorded for the 10 individual products. Thus, the variable X₅ for each criterion of the evaluation has the form

$$X_5^{synthetic}={\displaystyle \sum }_{i=1}^{10}{X}_{5\left(K\right)}^i$$

(2)

where:

K—Assessment criterion that stands for quality, esthetics, ease of use and energy efficiency. For each criterion to assess the products used, the X₅ variable may take values from 1 (each of the 10 analyzed products received the lowest score, i.e., 1—poor level) to 5 (each product received the highest score, i.e., 5—very good).

The calculations were conducted in the Statistica software purchased by universities under the Site License academic license. For the classification tree, the C&RT (Classification & Regression Trees) module was used, which is a complete implementation of the CART method introduced by Breiman and his colleagues from Berkeley [60].

4. Results and Discussion

Of the total number of respondents (owners/users of durable products for at least 2 years) who answered the questionnaire, 72% were women and 28% were men. This group was dominated by people aged 30–49, who constituted 41% of the sample. The lowest percentage of respondents was recorded in the case of the oldest age groups: for people aged 50–69, it was 9%, and for people aged 70 and older, it was 3%. More than 2/3 of the respondents declared the net income per person in their household with a value of, at most, PLN 4000 (including the net income for about half of the people, which ranged from PLN 2001 to PLN 4000). When considering the place of residence of the respondents, 75% were urban residents, including 39% who were inhabitants of cities with more than 100,000 inhabitants.

According to the information collected, 32% of respondents declared that they had purchased at least one durable product in the last two years. This subset was dominated by consumers who noticed the problem of the deliberate aging of products by producers so that customers would buy more often (they accounted for 64.5%). Over 10 times fewer respondents did not notice this problem, including not a single respondent who definitely did not agree with the occurrence of such a phenomenon (see

Table 1. Opinions of respondents on the deliberate aging of products and the differences in product quality in Poland compared to the period before 1990 or compared to products from Asia.

Specification	Manufacturers Deliberately Age Products So That Customers Buy Durable Goods More Often (Y)	Many Products Available on the Market in Poland Are of Lower Quality Than the Products Manufactured before the Political Transformation, i.e., before 1990. (X7)	Products Manufactured in Asia Are Less Durable Than Those Made in Poland (X8)
	[%]
Definitely no	-	2.5	0.8
Rather no	5.0	7.4	14.9
Hard to say	13.2	9.1	23.1
Rather yes	33.9	31.4	25.6
Definitely yes	30.6	31.4	17.4
No answer	17.4	18.2	18.2

Source: own study.

).

According to nearly 63% of the consumers in the survey, many products available in the market in Poland are of a lower quality than the products manufactured before the political transformation, i.e., before 1990 (compared to 10% of consumers who did not agree with this statement) (see Table 1). It is worth noting that the percentage of consumers who noticed the problem of the deliberate aging of products by producers was different among buyers of individual products in the last two years. This problem was most noticed by respondents who, in the last two years, purchased products such as a washing machine, a mobile phone and, the least, a TV set, a cooker or a car (see Figure 1).

For most products, functionality and durability were the main determinants of purchases: for instance, in the case of purchasing a washing machine or a cooker (see

Table 2. Main determinants of purchases of selected durable products.

Product	Percentage of Respondents for Whom the Main Purchasing Determinant Was:
	Price	Appearance	Functionality	Durability	Brand	Innovativeness	Quality
	%
Washing machine	28.9	13.2	43.8	34.7	14.9	12.4	31.4
Mobile phone	21.5	29.8	47.1	24.0	24.0	24.0	24.8
Refrigerator	23.1	27.3	38.8	36.4	12.4	10.7	27.3
Vacuum cleaner	23.1	9.9	47.9	24.0	11.6	14.9	24.8
Kettle	22.3	28.9	22.3	20.7	5.8	6.6	12.4
Dishwasher	13.2	9.9	30.6	28.9	6.6	6.6	21.5
Computer	21.5	19.8	37.2	23.1	15.7	17.4	24.0
Car	28.9	28.1	26.4	28.1	22.3	14.9	24.8
Cooker	16.5	21.5	35.5	28.1	6.6	13.2	24.0
TV	16.5	21.5	28.9	21.5	16.5	21.5	23.1
Bicycle	24.8	24.8	22.3	18.2	7.4	5.8	18.2

Source: own study.

). However, in the case of a kettle or a mobile phone, the look was the main determinant, and in the case of a car purchase, the price was the main determinant. The results confirm that the distribution of determinants varies depending on the respondents’ income (see Figure 2). In particular, for the vast majority of items, for a lower income level, the most important determinant among those analyzed when buying items was the price (especially in the case of a washing machine, a car or a computer). The respondents had different preferences when buying a cooker, a mobile phone and a bicycle. Even with lower incomes, innovation (when buying a cooker or a mobile phone) and durability (when buying bicycle) played a big role in these cases. On the other hand, people with the highest incomes were guided by the brand (except for the purchase of a car, in the case of which, irrespective of income, the price is of great importance).

In the next stage of the analysis, for the subset of respondents who declared that they had purchased durable products, the following multi-way table (

Table 3. Opinions of respondents on the deliberate aging of products depending on the expected life of the equipment used.

Estimated Length of the Functioning of the Used Equipment Compared to the Assumed Time on the Day of Purchase (X4)	The Degree of Acceptance of the Phrase “Manufacturers Deliberately Age Products So That Customers Make Purchases More Often” (Y)					Total
	Rather No	Rather Yes	Hard To Say	Definitely Yes	No Answer
Definitely shorter than T *	-	-	-	1	-	1
Rather shorter than T	2	1	6	7	4	20
Neither longer nor shorter than T	-	5	10	11	3	29
Rather longer than T	3	8	21	14	11	57
Definitely longer than T	1	2	4	4	3	14
Total	6	16	41	37	21	121

* T—assumed time on the day of purchase. Source: own study.

) presents the frequency of responses in terms of the expected length of operation of the used equipment compared to the assumed time on the day of purchase, and in terms of opinions on the deliberate aging of products by manufacturers.

In the analyzed subset of respondents, 59% expected that the purchased product would function longer than the assumed time on the day of purchase, while the second group, representing 17% of the respondents, expected that the purchased product would function for a shorter period of time. The distinguished groups of respondents differed in the frequency of perceiving the problem of product aging by producers. A total of 61% of the respondents from the first group agreed with the statement that producers deliberately aged their products so that customers would buy more often (25% strongly agreed). This percentage in the group of people expecting a shorter period of functioning of the purchased products was slightly higher—67% (including 38% definitely agreeing with the above statement).

The 324 users of the durables covered by the survey were also asked about what they would do if the product broke after the warranty period. The following results were obtained: purchase a new one and dispose of the defective product—15.1%; purchase a new one and store the broken product at home—5.7%; and repair broken equipment and continue its use—18.8%.

The distributions of respondents’ answers presented in

Table 4. Structure of attitudes of respondents’ opinions in terms of perceiving the problem of deliberate product aging by producers in subgroups determined by the type of declared behavior when the product broke after the warranty period.

Opinion on the Correctness of the Phrase “Manufacturers Deliberately Age Products So That Customers Make Purchases More Often” (Y)	Procedure When the Product Breaks Down after the Warranty Period (X6):
	Purchase a New One and Throw Away the Broken Product	Purchase a New One and Store the Broken Product at Home	Repair Broken Equipment and Use It Further
Rather no	2	1	5
Hard to say	9	6	8
Rather yes	20	6	29
Definitely yes	15	5	25
No answer	12	4	5
Total	58	22	72

Source: own study.

indicate structural differences between the distinguished groups. The problem of product aging was most noticed in the group of people who declared that they had repaired broken equipment and that it would be continued to be used if the product broke after the warranty period—75% (answers “yes” and “definitely yes”). Among people who declared buying a new product and storing a broken product at home, this percentage was 50%, while among people who bought a new product and threw away the broken product, it was 60%.

Based on the responses of the respondents presented in

Table 5. Self-assessment of owned and used products in the household in terms of: quality of workmanship, esthetics and energy efficiency.

Product	Average Score *			Percentage of Respondents for Whom the Product Was Rated at Least Good
	Quality	Esthetics	Energy Saving	Quality	Esthetics	Energy Saving
Washing machine	4.36	4.29	4.06	87.0	84.4	73.1
Refrigerator	4.43	4.46	4.07	89.6	89.0	76.5
Vacuum cleaner	4.05	3.96	3.85	76.6	71.5	66.0
Dishwasher	4.35	4.37	4.04	86.2	83.7	77.7
Cooker	4.38	4.30	4.05	86.1	83.3	74.3
TV	4.53	4.56	4.09	90.8	91.4	74.2
Car	4.31	4.21	3.70	88.5	84.0	64.3
Computer	4.50	4.53	4.07	89.9	88.0	75.5
Mobile phone	4.57	4.66	4.12	91.8	91.8	76.1

* A 5-point grading scale was used: 1—very poor level, 2—poor, 3—satisfactory, 4—good, 5—very good. Source: own study.

, in terms of their self-assessment of owned and used selected products in a household, it was found that most of the products’ highest rating related to the quality of workmanship, while the worst rating was in terms of energy efficiency. The opinions obtained from users of durable goods differed according to the type of product. On average, in terms of the quality of workmanship and esthetics, mobile phones and TV sets had the highest scores, and vacuum cleaners had the lowest; in terms of energy efficiency, the lowest scores were recorded for cars and vacuum cleaners, and the highest for dishwashers and refrigerators.

In order to verify the relationship between the dependent variable, namely, the perception of the problem of the deliberate aging of products (Y), and the explanatory variables selected for analysis (X₁, … X₁₂), e.g., selected respondents’ attitudes or control variables, the Pearson chi-square test of independence was applied. The results of the calculated values of the test statistics (Pearson chi-square or NW chi-square) and p-value (p value) for individual variables are presented in

Table 6. Results of the chi-square test of independence for the dependent variable Y and the selected explanatory variables X_i.

Variable Xi	$\mathbf{Value} {\mathit{\chi }}^2$	p-Value
Gender (X9)	0.234	p = 0.628
Age (X10)	8.756 *	p = 0.032 *
Education (X11)	0.476	p = 0.788
Net income per person in the household (X12)	0.307	p = 0.958
Place of residence (X13)	0.778	p = 0.854
Purchase of any durable product in the last two years (X1)	3.781 *	p = 0.050 *
Self-assessment of the duration of operation of the equipment used compared to the assumed time on the day of purchase (X4)	3351	p = 0.500
Belief in the correctness of the phrase: “many products available in the market are of a lower quality than the products manufactured before the political transformation, i.e., before 1990” (X7)	10.352 *	p = 0.0348 *
Belief in the correctness of the phrase: “products manufactured in Asia are less durable than those made in Poland” (X8)	4.746	p = 0.314
Procedure when the purchased product breaks down after the warranty period:
Purchase a new one and throw out the broken one (X6, a new one–broken out)	0.049	p = 0.825
Purchase a new one and store the broken product at home (X6, a new one–broken at home)	2.647	p = 0.104
Repair broken equipment and continue its use (X6, no new one–repair broken one)	7.200 *	p = 0.007 *

Source: own study. * The test result is statistically significant (significant relationship between X_i and Y).

and

Table 7. The results of the chi-square independence test for the dependent variable, namely, perceiving the problem, and the variable regarding the choice of durability or price as a purchasing determinant.

Product	The Main Determinant of Purchasing a Product—Durability X2 (Durability)		The Main Determinant of Purchasing a Product—Price X2 (Price)
	$\mathbf{Value} {\mathit{\chi }}^2$	p-Value	$\mathbf{Value} {\mathit{\chi }}^2$	p-Value
Washing machine	3.393 *	p = 0.065 *	6.237 *	p = 0.0125 *
Refrigerator	3.963 *	p = 0.046 *	5.486 *	p = 0.019 *
Vacuum cleaner	2.609	p = 0.106	2.688	p = 0.101
Kettle	0.101	p = 0.751	5.080 *	p = 0.0242 *
Dishwasher	0.205	p = 0.650	4.415 *	p = 0.035 *
Cooker	6.021 *	p = 0.014 *	2.646	p = 0.103
TV	2.850	p = 0.091	2.646	p = 0.103
Mobile phone	0.007	p = 0.932	1.499	p = 0.220
Computer	1.502	p = 0.220	3.484	p = 0.0619

Source: own study. * The test result is statistically significant (significant relationship between X_i and Y).

.

The applied ${\chi }^2$ test showed the existence of a correlation between the dependent variable, namely, the perception of the problem of the deliberate aging of products, and the variables: (1) belief in the correctness of the phrase: “many products available in the market are of a lower quality than products manufactured before the political transformation, i.e., before 1990”; and (2) in a situation where the purchased product broke after the warranty period, one would repair the broken equipment and use it further. Moreover, a significant relationship was found between the dependent variable and the control variable of age.

Considering the main determinants of purchasing the selected durable products declared by the respondents, on the basis of the value of the relevant test statistics, a relationship between variables—noticing the problem of the deliberate aging of products (Y) and deciding to purchase mainly based on price in relation to a washing machine, a refrigerator, an electric kettle and a dishwasher—was found. In the case of the variable relating to durability as the main determinant of purchases, a significant relationship occurred for the purchase of a washing machine, a refrigerator and a cooker.

In this paper, the development of a classification tree was carried out in order to verify the significance of the influence of the relation of each explanatory variable (X_i, i = 1, … 12) on the dependent variable (Y) and to define disjoint segments and qualitative classes of the dependent variable (Y, perceiving the deliberate aging of products by producers) on the basis of measurements of explanatory variables (X_i, i = 1, … 12, i.e., selected attitudes and behaviors of buyers of durable goods). During the construction of the model, cases of non-responses were omitted. As a result of the development of the classification tree, a ranking of the importance of variables (

Table 8. Ranking of importance of variables relating to durability.

Variable	Importance
Belief in the correctness of the phrase: “many products available in the market are of a lower quality than the products manufactured before the political transformation, i.e., before 1990” (X7)	100
Price is the main determinant of purchasing durable products X2 (Price)	57
Durability is the main determinant of purchasing durable products X2 (Durability)	54
Self-assessment of owned and used products in the household in terms of energy efficiency X5 (Energy efficiency)	53
Belief in the correctness of the phrase: “products manufactured in Asia are less durable than those made in Poland” (X8)	51
Self-assessment of owned and used products in the household in terms of the quality of workmanship X5 (Quality)	49
Self-assessment of the duration of operation of the equipment used compared to the assumed time on the day of purchase (X4)	44
Self-assessment of owned and used products in the household in terms of esthetics X5 (Look)	44
Procedure in case the product breaks down after the warranty period: repairing the broken equipment and using it further, described by the variable X6 (no new one–repair broken one)	39
Age (X10)	37
Net income per person in the household (X12)	37
Procedure in case the product breaks down after the warranty period: buying a new one and storing the broken product at home, X6 (a new one–broken at home)	37
Place of residence (X13)	23
Education (X11)	11
Purchase of any durable product in the last two years (X1)	8
Gender (X9)	6
Procedurę in case the product broke after the warranty period: buy a new one and throw away the broken product, X6 (a new one–broken out)	6

Source: own study.

) based on one-dimensional divisions (where 0 means low importance, and 100 means high importance) was obtained.

According to the model obtained (Figure 3) and the ranking of explanatory variables (Table 8), the following factors had the greatest impact on the perception of the problem of the deliberate aging of durable products: (1) belief in the correctness of the phrase: “many products available in the market are of a lower quality than the products manufactured before the transformation system, i.e., before 1990, and (2) being guided by price and durability when making purchases. The gender of the respondent turned out to be the least significant, along with the manner and procedure in case the product broke after the warranty period: buying a new one and throwing away the broken product. Finally, after applying the adopted stop rule, six significant variables were taken into account in the structure of the classification tree, which had the highest classification power when creating the model (which is equivalent to the fact that they were crucial in the division of the entire population into classes of respondents, which differed significantly in terms of perceiving the problem of the deliberate aging of products). As a result of the procedure carried out, using appropriate measures of the quality of the division of the analyzed group of respondents according to the assessment of products’ condition, 10 classes of respondents were distinguished (C₁, … C₁₀)—see end nodes (lists) in Figure 3 and the set of classes of respondents in

Table 9. Classes of respondents agreeing with the statement about the deliberate aging of products by producers so that customers buy durable goods more often.

Class	Characteristics	People Share
C1	Number = 21 units (18% of the studied subset). The price was not taken into account when purchasing any durable product. It was expected that the possessed durable products would function longer than the assumed time on the day of purchase.	38%
C2	Number = 1 unit (approximately 1% of the studied subset). The price was not taken into account when purchasing any durable product. It was not expected that the possessed durable products would function longer than the assumed time on the day of purchase. For 8 or fewer products out of 10 analyzed, durability was the main determinant of purchases. No opinion on the lower quality of products available in Poland than before 1990.	0%
C3	Number = 22 units (19% of the studied subset). The price was not taken into account when purchasing any durable product. It was not expected that the possessed durable products would function longer than the assumed time on the day of purchase. For 8 or fewer products out of 10 analyzed, durability was the main determinant of purchases. They agreed with the statement that many products available on the market in Poland are of a lower quality than products manufactured before 1990.	90%
C4	Number = 4 units (3% of the total number of respondents). The price was not taken into account when purchasing any durable product. It was not expected that the possessed durable products would function longer than the assumed time on the day of purchase. For over 8 products out of 10 analyzed, durability was the main determinant of purchases.	25%
C5	Number = 7 units (6% of the total number of respondents). When buying at least one durable product, the price was the main determinant. They disagreed with the statement that many products available on the market in Poland are of a lower quality than products manufactured before 1990.	57%
C6	Number = 9 units (8% of the total number of respondents). When buying at least one durable product, the price was the main determinant. They agreed with the statement that many products available on the market in Poland are of a lower quality than the products manufactured before 1990 (or there was no opinion on this subject). In a situation where the product broke after the warranty period, the broken equipment was repaired and used further.	89%
C7	Number = 3 units (3% of the total number of respondents). When buying at least one durable product, the price was the main determinant. They agreed with the statement that many products available on the market in Poland are of a lower quality than the products manufactured before 1990 (or there was no opinion on this subject). In a situation where the product broke after the warranty period, new equipment was purchased.	33%
C8	Number = 13 units (11% of the total number of respondents). When buying at least one durable product, the price was the main determinant. They strongly agreed with the statement that many products available on the market in Poland are of a lower quality than products manufactured before 1990. Net income per person in the household ranged from PLN 2001 to PLN 4000.	100%
C9	Number = 1 unit (about 1% of the total number of respondents). When buying at least one durable product, the price was the main determinant. They agreed with the statement that many products available on the market in Poland are of a lower quality than the products manufactured before 1990 (or there was no opinion on this subject). Net income per person in the household ranged from PLN 2001 to PLN 4000.For all products, price was the main determinant of purchases.	0%
C10	Number = 26 units (22% of the total number of respondents). When buying at least one durable product, the price was the main determinant. They agreed with the statement that many products available on the market in Poland are of a lower quality than the products manufactured before 1990 (or there was no opinion on this subject). Net income per person 4001 PLN and more.	100%

Source: own study.

.

5. Conclusions

Durable goods have become common and widely available products for households. According to this survey, every third respondent purchased a DTU in the last two years. Restitution purchases of products generate the need to pay attention to the price, durability, functionality, brand and look. These determinants depend on the type of product. Therefore, for example, when buying a kettle or a mobile phone, the look is important, and when buying a car, the price and the look are important. The results confirm that the ranking of purchasing determinants changed depending on the respondents’ income. Important/significant determinants of purchases also turned out to be innovation (when buying a cooker or a mobile phone) and durability (when buying a bicycle), and in the case of a subset of people, respondents with the highest income were guided by the brand (apart from buying a car, in which, regardless of income, the price is important). A total of 65% of the respondents noticed the problem of the deliberate aging of products. Over 60% of the respondents took the position that the products produced in the autarkic economy (before 1990) were more durable and their life cycle was much longer.

This research indicates the features of durable products that are desired by consumers (durability, functionality, price, look, brand). This results in managerial implications: taking up measures to reduce the strategies of shortening the life of products (i.e., focusing on durability and long-term functionality) will contribute to the improvement in the company’s position in the market as an enterprise responding to consumer expectations and that, at the same time, is environmentally friendly. A special role in terms of practical implications is played by building eco-energy awareness of purchased products among young people, as in the future, they will be responsible for implementing energy-saving solutions in their households and the entire economy [66]. These activities are in line with the sustainable and circular economy system. Generating sales by shortening the life of products is unethical and also unprofitable. In the era of transparency of information and opinions issued on the Internet by users, customers will buy valuable products. Increased awareness of buyers who evaluate the value of products with a short lifetime and are aware of their short lifetime affects the rational management of energy resources in the household. The production of subsequent devices with a short lifetime translates into additional energy consumption because the production of each new product means a certain energy cost and additional emissions of pollutants into the atmosphere, resulting from the production process of all the necessary elements.

The results of this research indicate the growing awareness of consumers in the field of responsibility for the environment and sensitivity to the issues of ecological, sustainable development. Therefore, re-evaluating the existing strategies and promoting an economy based on the reuse and repair of products seems to be an increasingly urgent challenge. However, for consumers to trust producers, legal solutions should be introduced. They should ensure transparency of solutions and implement the possibility of institutional quality control of durable goods.

The proposed method of classification trees showed, inter alia, that among the distinguished classes of respondents in terms of attitudes towards preferences when purchasing durable goods, there were classes consisting mainly of people who noticed signs of planned aging of products. Their common feature was that when shopping, they were guided mainly by price and the belief that many products currently available in the Polish market are of a lower quality than products manufactured before 1990.

This research did not identify the purchasing attitudes of durable goods buyers. The conducted questionnaire study was exploratory. This pilot study also allowed testing the possibility of applying the proposed analytical method (classification trees), which could be used in the actual study, with a much larger size, taking into account the categorical dependent variable in the model without converting it into a binary variable.

In subsequent studies, it is recommended to conduct in-depth research on an extended sample and to extend the territorial scope to the international dimension. Moreover, taking into account the importance of the problem under consideration, it is justified to monitor consumers’ attitudes towards the aging of products on an ongoing basis. In this aspect, it is important to study changes in environmental awareness and the level of responsibility for the consequences of the choices made (including paying attention to consumers’ tendency to perceive consumption in a qualitative manner).