Independent User Circular Behaviors and Their Motivators and Barriers: A Review

Abstract

The promotion, facilitation, and adoption of circular behaviors are extremely vital for the success of the transition toward a Circular Economy. Thus, many studies have been conducted on circular behaviors and designing for them. Nevertheless, most of the previous studies adopted a macro perspective (across different business models and product types) to investigate circular behaviors related to product purchasing, product disposal, or a particular circular strategy, such as repair or recycling. Intending to address a serious gap, this study aimed to identify a specific, important set of circular behaviors: independent user circular behaviors. These are the behaviors that can be solely performed by the same product user, during use or at the end of the product life, in relation to a shopping product owned under a product-oriented or pure product business model. After critically reviewing the key literature, we present a model for independent user circular behaviors (CURA model). It includes four behaviors: care, upgrade, repurpose, and appreciate. The latter is a concept we are introducing in this paper. We also identified and categorized the motivators of, and the barriers to, these behaviors. The study outcomes are hoped to encourage and guide researchers toward an in-depth exploration of independent user circular behaviors. Moreover, they are expected to assist researchers, product designers, and business strategists in conceptualizing and realizing products of higher circularity, and, ultimately, stimulate sustainable consumption patterns.

1. Introduction

The mention of the term “Circular Economy” in scholarly writings may be traced back to 1990, when it was conceptualized for the first time by two British environmental economists, David W. Pearce and R. Kerry Turner [1]. Nevertheless, the origins of the Circular Economy concept are deep-rooted and cannot be traced back to a single author or date; various concepts have contributed to the development and the refinement of the current understanding of the Circular Economy. This includes cradle-to-cradle, industrial ecology, looped and performance economy, biomimicry, regenerative design, and the blue economy. The common aspect of all these theoretical influences is the notion of closed loops [2]. However, the Circular Economy is regarded as an operationalization for businesses to achieve the much-discussed and sought-after sustainable development; it is believed to be the vehicle to alleviate many of the environmental, economic, and societal burdens caused by the unsustainable, traditional, linear way of production and consumption. That is why the Circular Economy has been gaining traction both in academic research and on the agendas of practitioners and policymakers. This is reflected in the rapid increase of peer-reviewed articles on the Circular Economy, the many recent consultancy reports on the topic, and the influence it has had on governments and intergovernmental agencies at different levels (for instance, “The Circular Economy Promotion Law of the People’s Republic of China” came into force in 2009) [2,3,4].

It is assumed that the initial report on the Circular Economy published by the Ellen MacArthur Foundation (EMF), in January 2012, gave momentum to the discourse on this emerging concept. The report also coined the most prominent and frequently employed definition of the Circular Economy [2,3]: “an industrial system that is restorative or regenerative by intention and design” [5]. What this (and most of the definitions) lacks is the mention of consumers and business models as enablers of the Circular Economy [3]. Moreover, in general, research has not adequately investigated the role of user behaviors and the motivations behind them in a circular system [6]. This is a clear knowledge gap in the literature, and it is a serious gap because a circular economy is one in which products, their components, and materials are kept at their highest level of value and utilized to the maximum possible extent, for as long as possible, and finally recycled. As such, the transition to a Circular Economy greatly depends upon businesses’ adoption of circular business models, and users’ exhibition of certain behaviors when acquiring products, whilst using them, and at the end of their useful lives. Those behaviors are referred to as circular behaviors [7]. Nonetheless, the studies that have addressed the role of users in the transition to a Circular Economy have either focused on user circular behaviors related to one circular strategy (e.g., remanufacturing, recycling, or repair) [8,9,10] or investigated circular behaviors associated with a particular product phase (purchasing or end-of-life) [6,11]. Moreover, most of the studies considered circular behaviors across different business models, several stages of the product lifecycle, and many product categories [7,12]—to cite but a few. Surely, such studies have contributed to an enhanced, broad understanding of the interactions (as well as the intersections) between governmental policies, companies’ business models, product design, and user circular behaviors. However, we believe that there is a need for a more narrow-scoped study. One that focuses separately on each of the overlapping areas between the aforementioned elements in order to gain an in-depth understanding and to propose suitable aiding tools and design interventions.

The main objectives of this study are, first, to identify the user circular behaviors that could be independently performed by an individual user of a product (either by themselves or through a service) without needing to interact with other users (these behaviors will be referred to as independent user circular behaviors); then, to identify the barriers and the motivators of those behaviors. However, the only consumer products considered in this study are shopping products, such as electronics, clothing, and furniture [13,14] that are acquired within a product-oriented or pure product business model [15]. Furthermore, the scope of this research is limited to user circular behaviors carried out during use or at the end of the product lifecycle. In other words, circular behaviors exhibited by the user during the purchasing of the product are out of the scope of this study (Figure 1) as they are primarily influenced by factors beyond product design (e.g., marketing, packaging, and labeling) [6]. As far as the authors are aware, no previous study has delineated these essential user circular behaviors. Additionally, the extraction (from the literature), the synthesis, and the categorization of the motivators and barriers to these behaviors will also be an original contribution to the expanding knowledge of the Circular Economy and its related strategies and practices. The outcomes of this study should help designers and business strategists envision and realize novel, circular value-creating, and value-capturing ideas.

The remainder of this paper is structured as follows. Section 2 presents a review of the literature outlining Circular Economy strategies, circular business models, and the associated user circular behaviors within the overall scheme of a circular system. Section 3 illustrates the methods employed to identify the independent user circular behaviors, their motivators, and the barriers that would discourage or prevent users from performing them. Section 4 presents the results of the study and the discussion of the results. Finally, in Section 5, the paper concludes with a recap of the results, remarks on their significance and the contributions of this study, an acknowledgment of a limitation to the study, and interesting ideas for future research.

2. Literature Review

In this section, key literature on circular strategies, relevant circular business models, and related user circular behaviors is critically reviewed. The first subsection discusses circular behaviors related to R frameworks, particularly the renowned 9R framework (around which the writing of this subsection is organized). In the second subsection, two essential user circular behaviors beyond the 9R framework are discussed.

2.1. Behaviors Related to the R Frameworks

The main strategies in a circular economy have been depicted by several R frameworks, which are viewed by many authors as practical guides for a Circular Economy and have been used in academia as well as the industry. Among those, the most prominent framework is the 3R framework, which illustrates Circular Economy as a combination of reduce, reuse, and recycle. Another framework is the 4R framework, which encompasses the previous 3Rs in addition to ‘recover’. A more comprehensive framework, however, is the well-known and frequently cited 9R framework [3]. It first appeared in an article that aimed to discuss the challenges of transitioning to a circular economy in the Netherlands. The author outlined what she called the nine levels of circularity, descending from high to low levels of priority. These were namely: refuse, reduce, reuse, repair, refurbish, remanufacture, repurpose, recycle, and recover [16]. The framework was then adapted by Potting et al. [17], who added ‘rethink’ to the strategies outlined by Cramer. Thus, in total, the framework encompasses 10 strategies; but, the first strategy, ‘refuse’, is coded as R0, whereas the last strategy, ‘recover’, is coded as R9.

In the 9R framework (Figure 2), the last two strategies (recover and recycle) are about finding useful applications for the product materials. They are the last resorts in the waste hierarchy and the lowest levels of circularity [3,16]. Recycling involves converting products into raw materials and then chemically reprocessing them [18]. This requires the implementation of legislative stipulations and the employment of a waste management system at the country level to ensure the collection of the right volumes and types of recyclable materials from municipal waste and their transport to an industrial facility [19,20,21]. In this regard, users’ participation is essential for the success of the strategy as it increases the efficiency of the collection of end-of-life products [6]. Moreover, users are sometimes required to separate waste at home and then travel to specific recycling collection points to drop it off. On the other hand, recovery is basically the incineration of waste materials that cannot be recycled [18]. For that reason, it is regarded as a complementary strategy to recycling [22].

The first three strategies in the 9R framework (reduce, rethink, and refuse) are about product design, manufacturing, and use decisions aiming to reduce the consumption of natural resources or to find smarter uses for the products [3,22]. ‘Refuse’ is to reject the product itself and offer its function through a completely different product (for instance, a nonmaterial one: a digital product). Morseletto [22] stated that this strategy could also be about refusing certain materials or specific production processes. ‘Reduce’ is concerned with narrowing resource loops and using less energy and raw materials [22,23]. Morseletto [22] highlighted that this strategy is a less extreme form of ‘refuse’, and that it could be extended to limiting the production rates of new products (such as cars) to encourage ‘reuse’. However, unlike the previous two strategies, ‘rethink’ pertains to product use. Kirchherr et al. [3], Morseletto [22], and Kumar Mangla et al. [18] defined ‘rethink’ as intensifying product use through sharing it among many users. But Morseletto [22] elaborated that ‘rethink’ has a wider connotation, one that includes reconceptualizing concepts, processes, uses, and the subsequent post-uses of products.

Based on the definitions and the discussion in the previous paragraph, it could be correctly inferred that there are user circular behaviors related to the ‘rethink’ strategy. Kumar Mangla et al. [18] outlined leasing, renting, and sharing as the main approaches to rethinking product use. These are subcategories within the use-oriented business model. In this model, the company owns the product and gains profit by making it available to users through leasing, renting, sharing, or pooling (i.e., users can simultaneously use the product) [15]. In terms of economics, Tukker [15] argued that rented, shared, and pooled products probably have a significantly lower market value than competing products because of the tangible and intangible sacrifices the user has to make when sharing the product with others. However, from an environmental point of view, Tukker [15] suggested that, in principle, renting, sharing, and pooling could yield high environmental gains, whereas leasing can lead to undesirable user behaviors and increase the environmental burdens.

The use-oriented business model is one of three main new business models called product-service systems (PSS) business models. They are advocated for by many authors as a promising means to encourage sustainability and enhance circularity—according to Michelini et al. [24] and Tukker [15]. The other two main types of PSSs are product-oriented and result-oriented business models [15]. After reviewing the literature on PSSs and conducting a bibliometric analysis, Michelini et al. [24] concluded that authors consider result-oriented PSS as the only business model of real contributions to circularity. This was attributed to the fact that the user will only pay for a desired result while the product ownership remains with the company (or the firm), and after delivering the service to the user, the company can utilize the product or its modules for a different service, thus increasing circularity. However, Tukker [15] regarded function-oriented PSS (which is a subtype of the result-oriented PSS model) specifically as the most environmentally promising PSS type.

In general, regarding PSSs in which the ownership of the product is retained by the provider, there are many behaviors expected of users, and other behaviors that are undesired (during use and at the end of the product lifetime). Wastling et al. [7] identified and classified user behaviors in relation to products owned by the provider:

• During product use, users are expected to take care of the product by themselves or through engagement with the company’s after-sales services (such as life extension services). In addition, users are expected to provide the company with information about the state of the product at the start of its use (to confirm that the previous user left the product in a good condition) and during its use (to make the provider aware of any damage or need for maintenance). Wastling et al. [7] also identified two behaviors to be avoided: using the product for tasks other than the ones it was designed for (misuse), and any behavior that could destroy the product (damaging).
• At the end of use: it is desired that users return the product on time and in a satisfactory condition for the next use. Moreover, users’ assistance with reverse logistics might be required. For instance, instead of collecting the product from the user, the company might demand that the user take the product to a post office [7].

All the previous behaviors are within the use-oriented or result-oriented PSS business models. However, Tukker [15] argued that the product-oriented PSS business model is, still, the easiest to introduce and the best to be implemented by companies aiming to achieve incremental environmental gains. Among the different PSS types, product-oriented is the closest to the classic, pure product business model, which is geared toward making revenue from selling more products. However, in the product-oriented PSS business model, the company adds extra services around the product [15]. This type of PSS is related to the five middle strategies in the 9R framework (concerned with product and component lifetime extension). In the following paragraphs, we will discuss these strategies and the user circular behaviors related to them.

As presented in the 9R framework, the five product life extension strategies are namely: reuse, repair, refurbish, remanufacture, and repurpose. ‘Reuse’ is an essential Circular Economy strategy. It is one of the inner technical loops of the Circular Economy system diagram (famously known as the butterfly diagram) [5]. The strategy is present in every R framework, including the 3R framework (reduce, reuse, recycle) and its variations, such as (reuse, remanufacture, recycle) [3,25,26]. ‘Reuse’ involves having an old product (which is in a good condition) used by another user to fulfill the same function [3]. However, Morseletto [22] distinguished between two types of ‘reuse’: The first type is when the product’s ownership changes from one user to another after the product is gifted, resold, or discarded. The second type of ‘reuse’ is related to products within a PSS business model, where the company contracts the product to different users at different times. The author argued that in the first case, the exhibition of the behavior depends upon the user’s predisposition to use a second-hand product [22].

According to Cramer [16], to refurbish is to “improve the product”. Relatedly, Kirchherr et al. [3] define ‘refurbish’ as “restore an old product and bring it up to date”. Refurbishing, typically, involves replacing parts of the product, but it rarely involves disassembly [22]. Remanufacturing, on the other hand, is a process that involves “disassembling, cleaning, inspecting, repairing, replacing, and reassembling the components of a part or a product in order to return it to an ‘as-new’ condition” [27]. That is why remanufacturing is also called second-life production, whereas refurbishing is called light remanufacture [22]. In their article, Lüdeke-Freund et al. [28] described remanufacturing and refurbishing as “more comprehensive overhauls”. Both strategies require companies to incorporate reverse logistics in their business models to collect used products and components, then reprocess them into products of as-new quality, to be sold at lower prices [28,29]. Users would have some role to play in such a business model; however, typically, refurbishing and remanufacturing are executed by, respectively, the product seller or manufacturer in their facilities and not by individual users in their places of work or residence [30].

Repair strategy includes repair and maintenance conducted to fix the product defects in order to keep using it for its original function [3]. Here, it is important to mention that Morseletto [22] correctly noted that “maintenance”—in the definition of repair provided in the 9R framework—does not mean keeping the product sound while it is still functioning. Rather, it is a form of repair, and in some cases, maintenance could include repair in addition to other activities [22]. Nevertheless, preventive, or predictive, maintenance is surely a user circular behavior (as outlined and discussed by Wastling et al. [7], Ackermann [31], Haines-Gadd et al. [32], and others). It is a user behavior that contributes to extending the product’s life and ultimately slowing resource loops.

Finally, from amongst the 9R strategies, product repurposing stands out as a cost-effective and less process-intensive strategy. It is defined as transforming the product, its components, or materials to serve a new purpose after it has fulfilled its first purpose [33]. Compared to other strategies, product repurposing requires minimal or no energy to perform, fewer resources, and no transportation to industrial facilities (users can perform repurposing at their places). Consequently, its potential pollution is minimal. In addition to that, it could minimize the need for dedicating large spaces to landfills. Moreover, on the individual user level, it contributes to financial savings [34]. It is a circular strategy and a circular user behavior. However, despite its economic and environmental benefits, limited research has been conducted on product repurposing. Furthermore, the few studies on product repurposing have focused mainly on non-electrical, non-mechanical products.

Scott and Weaver [35] took a user perspective approach to investigate repurposing. The authors conducted in-depth interviews with users who practice different types of repurposing. They discovered that what motivates users to repurpose was not an affinity for sustainable consumption, but rather a combination of a desire to express oneself, an anticipated pleasure from the process, emotional attachment to the product, economic drive, social influences, and (to a lesser extent) the user’s environmental consciousness. Other authors explored a special type of repurposing: upcycling. It is characterized by an increase in the value of the product after repurposing [36,37]. Bridgens et al. [36] aimed to understand the contexts, motivations, barriers, and potential benefits of “creative reuse” (i.e., repurposing) and upcycling in affluent Western societies. The most interesting user motivation highlighted by Bridgens et al. was the availability of 3D printing technologies to produce any extra parts needed for the transformation. Equally interesting was the barrier of stigma toward making objects from waste. On the other hand, Sung et al. [37] focused only on the drivers and the facilitators of upcycling, and through an extensive literature review, the authors identified different personal, social, and situational determinants.

Other studies focused on the product-related factors that facilitate repurposing or encourage users to perform it. Aguirre [33] followed an ethnographic approach to investigate the practice of repurposing in 3 major cities and 12 communities in Mexico. Lai and Shu [38] considered do-it-yourselfers as lead users and analyzed 57 do-it-yourself (DIY) projects—shared online—of repurposing IKEA home furniture. The factors identified by these two studies could be summarized as follows: the product is modular and designed for disassembly, the product’s material is durable, the product’s components provide immediate functionality if dismantled, and (because of its geometry or symmetry) the product has an inviting affordance—one that stimulates the user to repurpose. Furthermore, Aguirre [33] identified the product-related barriers that would discourage people from repurposing, such as having sharp edges or containing hazardous materials.

2.2. Behaviors beyond the 9R Framework

According to Bocken et al. [39] and Lüdeke-Freund et al. [28], with regard to the technical cycle of the Circular Economy system, there are only two resource strategies for closing resource loops: recycling and repurposing. The two strategies are included in the 9R framework and were discussed in the previous subsection. We also discussed the user behaviors related to them as well as user behaviors related to slowing resource loops (such as reuse and repair). In this subsection, however, we will explore user circular behaviors related to slowing resource loops beyond the 9R framework strategies.

The first circular behavior (and an essential one) is postponing product replacement, which results in product longevity. Mugge et al. [40] argued that there are six barriers to this behavior: three technical reasons (partial loss of functionality, incompatibility with new products or services, or lack of compliance with the new legislations); and three reasons related to the user (upwards shift in user’s demands due to technological advancements, changes in user’s desires because of new fashion trends, or changes in the user’s personal life). Scott and Weaver [35] called the driver for replacing the product before the end of its usefulness “relative obsolescence”. The authors believed it occurs when the product is no longer satisfactory technologically, psychologically, or economically. However, the absence of user satisfaction with the product is the proximate cause of relative obsolescence. Khan et al. [41], on the other hand, outlined the root causes (these are what caused the lack of user satisfaction with the product)—namely, innovations in the market (technological), changes in the user’s perceived needs (psychological), and the high cost of maintenance and repair (economic).

The other user circular behavior beyond the 9R framework is product care. It includes all the activities a user can exhibit to prolong the lifetime of the product—mainly repair and maintenance activities [42]. Studies have shown that user product attachment is a strong motivation for both product care and postponing product replacement [40,42]. Moreover, performing product care (especially repair) is likely to prevent relative technological obsolescence, or perhaps prevent the absolute obsolescence of the product [43]. Moreover, it could be noted that there is a correlation between the affordability of product care (repair and maintenance) and the absence of economic obsolescence. However, product care cannot directly result in preventing the occurrence of psychological obsolescence as it comes about from the change in the user’s desires or perceived needs. This is an important deduction that we will come back to in the methods section.

3. Methods

A narrative review of the literature was conducted to identify both the independent user circular behaviors and their motivators and barriers. The rationale for employing a narrative review to identify the behaviors is self-evident since we were aiming to discern all the behaviors mentioned or discussed in key literature. On the other hand, regarding the motivators and the barriers, we decided to utilize a narrative review based on the premise that it is the appropriate type of review for integrating and interconnecting studies on different topics. Additionally, narrative reviews allow for synthesizing qualitative as well as quantitative studies that used various methodologies, regardless of the statistical significance of their results [44]. As such, we were able to consider a wide range of studies on the different identified behaviors. It is important to highlight that our review possesses some of the elements of a systematic review, such as defining the search terms, the search mechanism, and the exclusion/inclusion criteria [45]. These are rarely presented in narrative reviews [46], which is a problem we intended to avoid.

There is an overlap between the review conducted to identify independent user behaviors and the one conducted to extract the motivators and the barriers: the identified behaviors were used as search keywords to find studies on their motivators and barriers. Nevertheless, this section is divided into two subsections. The first subsection delineates the steps followed to extract the independent user circular behaviors from the literature and to develop the model. The second subsection illustrates the steps followed in the review, and the tools used to identify, categorize, and synthesize the motivators of, and the barriers to, independent user circular behaviors.

3.1. Independent User Circular Behaviors

To set the stage for an intensive narrative review, we first conducted a preliminary search of Elsevier’s Scopus database to find the most relevant, highly cited peer-reviewed review papers on the Circular Economy. We chose the Scopus database because it currently has wider coverage than Web of Science (WoS) and higher indexing and citation standards than Google Scholar (GS) [47]. We conducted our preliminary search using the string “circular AND economy”. The search yielded many articles. After reading the titles of the top twenty entries, three articles (the most relevant to our research) were selected. Then, based on the abstracts, we selected two articles (which we deemed as the most relevant and insightful) to be reviewed. One paper was an extensive analysis of 114 definitions of ‘Circular Economy’ [3], and the other explored the similarities, differences, and relationships between the concept of Circular Economy and that of Sustainability [2]. These two articles helped sharpen the scope of this research and provided guidelines, as well as keywords, for identifying independent user circular behaviors. Furthermore, some independent user circular behaviors were identified in these two studies, namely ‘repair’, ‘maintain’, and ‘repurpose’ [2,3]. At a later stage, during the model development, the authors decided to use the term ‘care’ instead of ‘repair’ and ‘maintain’, for reasons that will be laid out in the next paragraph.

Aiming to identify more independent user circular behaviors, we searched the Scopus database with the strings “circular behavior”, “circular economy AND behavior”, and “circular design”. Then, descending from the highest cited article, we checked the search results and excluded articles that were, based on their titles, clearly beyond the study’s scope. This includes, but is not limited to, studies related to fast-moving consumer goods, product packing, product purchasing, and circular business models that involve product sharing. Afterward, we read the abstracts of the publications that seemed relevant—and skimmed the whole paper when needed. The selected articles were studied carefully, and the scope of this research was used to filter the contents of the studies and extract the target independent user circular behaviors (Figure 3). Some of the reviewed articles led to the identification of other relevant articles (including works that were not peer-reviewed: reports and policy documents), which, in turn, were also reviewed. At this stage, the review included the following scholarly writings: EMF’s [5], Parajuly et al.’s [6], Wastling et al.’s [7], Corsini et al.’s [12], Bocken et al.’s [39], and Moreno et al.’s [48]. Works beyond these writings were identified and skimmed; however, they were not thoroughly reviewed as they did not include new behaviors that meet the identification criteria. This was considered an indication of reaching data saturation. In the end, the independent user circular behaviors were identified and defined as follows:

• Care: to conduct maintenance, repair, or any preventive or protective measure aiming to prolong the product’s lifespan [31,42]. We decided to use ‘care’ instead of the activities it includes (mainly repair and maintenance), to have our work aligned with the recent research by Ackermann [31], Ackermann et al. [42], and Ackermann et al. [49] who took a user perspective approach to explore product care within the realm of a Circular Economy. We believe that building on their work would contribute to the coherence and the convergence of the Circular Economy terminology. Moreover, by using the term ‘care’ we aim to avoid the confusion that may arise from using the activities it encompasses (repair and maintenance) instead. That is because in the 9R framework and the butterfly diagram, “maintenance” is not a proactive action—but ‘maintain’, the user behavior, is [5,22].
• Appreciate: to continue using a functioning, energy-efficient product as is. It is important to mention that we are proposing this new concept to describe this specific behavior to distinguish it from (a) the behavior of postponing product replacement through care or upgrade, and (b) the environmentally undesirable retention of energy-guzzling products [50]. To appreciate the product is basically to resist phycological obsolescence, which arises when the user ceases to find a symbolic or aesthetic value in the product [50] because of a change in the perceived needs of the user [41].
• Upgrade: to improve the product functionality and capability aiming to extend its useful life [41].
• Repurpose: to reuse the product, its materials, or components, as is or after transformation, to serve a new purpose when the product can no longer fulfill its original purpose. It should be noted that this definition includes only end-of-life repurposing.

In the next subsection, we will discuss the identification and the categorization of the motivators and barriers to these behaviors.

3.2. The Motivators and the Barriers

3.2.1. Identification

Google Scholar was utilized to find studies that took a user perspective approach to identifying the motivators of, and the barriers to, independent user circular behaviors. Here, we used the Google Scholar database as it has the highest coverage of academic literature [47]. Thus, using it ensured increasing the breadth of our search. Each of the three identified independent user circular behaviors (“care”, “upgrade”, or “repurpose”) was linked by the “AND” operator with the word “product”, and the words “motivations”, “motivators”, or “barriers”, to form effective search terms. Moreover, since ‘appreciate’ is a concept we are introducing in this paper (and there are no previous studies on this behavior specifically) we used the search terms “postpone replacement”, “lifetime extension”, users AND “prolong product”, or “product longevity” linked by the “AND” operator with the words “motivations”, “motivators”, or “barriers”. But we made sure to only extract the motivators and the barriers that are pertinent to ‘appreciate’ behavior as previously defined. With regard to ‘care’ behavior, we also included studies on the activities it encompasses, namely ‘repair’ and ‘maintenance’. The search terms were the words “repair” or “maintenance” linked by the “AND” operator with the word “product”, and the word “motivations”, “motivators”, or “barriers”.

To increase the novelty of our review and to strengthen its rigor we aimed to only select articles that explored users’ perspectives on the motivators and barriers through quantitative, qualitative, or mixed methods approaches. In other words, we decided to exclude literature reviews and articles that were solely based on artifact analysis or experts’ opinions. Nevertheless, we eventually made exceptions for three studies. One was a review and synthesis of relevant literature on upcycling [37], and the other identified barriers to product longevity through a comprehensive review [51]. The third exception was the inclusion of Haines-Gadd et al.’s [32] study, which involved interviews with different product design stakeholders from Philips Lighting (not users or potential users). We included these three studies for their unique and useful insights from different angles.

Table 1. The papers reviewed to extract the motivators of, and the barriers to, the identified behaviors.

Independent User Circular Behavior	Papers
Care	Ackermann’s [31]; Ackermann et al.’s [42]; Terzioğlu’s [10]; Laitala et al.’s [43]
Appreciate	Mugge et al.’s [40]; Mugge et al.’s [52]; Haines-Gadd et al.’s [32]; van Nes and Cramer’s [50]; Jensen et al.’s [51]
Upgrade	Ülkü et al.’s [53]
Repurpose	Aguirre’s [33], Lai and Shu’s [38], Bridgens et a.’s [36], Sung et al.’s [37], Scott and Weaver’s [35]

presents the papers from which the independent user circular behaviors were identified.

3.2.2. Clustering and Synthesis

In three different sessions, the collected data were analyzed by the means of an affinity diagram. First, all the motivators and the barriers were printed on small cards. The authors agreed upon making tangible cards and a physical affinity diagram (instead of using software) as it is believed to facilitate the analysis and make it more efficient [54]. In the first session, the motivators of all the behaviors were organized in four columns corresponding to the four behaviors: care, appreciate, upgrade, and repurpose—in the order presented. Then, we started combining the motivators cards that are related. The ones that were almost identical (i.e., almost had the same wording) were connected and highlighted with a blue sticker, whereas the factors that were, in a way, related were jointly highlighted with a yellow sticker (Figure 4). After distributing the cards, it was noted through observation that the motivators within each column could be divided into groups, based on their relation to the user, the product, the process, and other components. Therefore, we started clustering the motivators (along the columns) into distinct categories. We first created three categories. The rest of the motivators could have also been clustered into other groups; however, in the first session, the authors could not create more groups that would be clearly and distinguishably delineated. Moreover, it was noted that many of the motivators of ‘care’ were also motivators of ‘appreciate’ and vice versa. Therefore, we added a column between these two columns and entitled it ‘Both’. This helped distribute the cards in a more organized way and made the subsequent synthesis steps easier. In the second session, the authors came to a consensus on the categories into which the rest of the motivators should be divided—vertically. We classified the motivators into five categories. These are namely: user-related, user–product-related, user–process-related, product-related, and situational. The categorization of the motivators was completed in this session. In the third session—the last one—the barriers were distributed along four columns (corresponding to the four behaviors) and, within each column, vertically clustered into five distinct groups (corresponding to the five categories into which the motivators were previously clustered). Then the same synthesis process was repeated to categorize the barriers cards.

Afterward, utilizing spreadsheets in Microsoft Excel, the motivators were further synthesized. First, a spreadsheet was created for each category (user-related, user–product-related, user–process-related, product-related, and situational). Then, all the motivators from that category were distributed vertically within the first column (one motivator in each cell). Next to the motivators column, four columns corresponding to the four independent user circular behaviors were created, and each motivator was mapped to the related behavior by adding a background color to the cell at the intersection of the motivator row and the behavior column. After that, similar motivators were synthesized (in one wording) in one cell and mapped to the behaviors they motivate (by coloring the corresponding cells). This was repeated for the other four categories of motivators. After concluding the synthesis of the motivators, the same process (using Microsoft Excel spreadsheets) was followed to further synthesize the barriers. After that, the motivators and the barriers belonging to the same category were combined in one table. This resulted in producing five tables. Each table contains the motivators and barriers that fall under one of the five categories: user-related, user–product-related, user–process-related, product-related, and situational. In each table, every motivator (or barrier) is mapped to the behavior(s) it stimulates (or discourages from or hinders) by a shaded cell where the corresponding column and row intersect. The tables will be presented in the subsequent section.

4. Results and Discussion

The identified independent user circular behaviors are presented in the independent user circular behaviors model (CURA model) (Figure 5). CURA is an acronym formed by combining the first letters of the terms ‘care’, ‘upgrade’, ‘repurpose’, and ‘appreciate’, respectively. This is not the order in which the behaviors are presented in the model; however, we have chosen this acronym because in Latin, ‘cura’ means cure [55], and we anticipate that the adoption of these behaviors by users would cure the current “throwaway culture” [56] of unsustainable practices related to the linear economy.

The introduction of the ‘appreciate’ concept is basically a delineation of a behavior encompassed within the practice of postponing product replacement. However, unlike the latter, to ‘appreciate’, users do not need to perform any activity other than to continue using the still-functioning, energy-efficient product as is. This concept is discerned at the heart of the domain identified by Bakker et al. [30]—among three domains—as the source for reasons to design long-lasting products. Bakker et al. described this domain as the affinity of humans with their stuff. As such, ‘appreciate’ could be thought of as the behavior of cherishing the product’s familiarity and the sentiments it evokes and resisting the craving for newness. This concept would enhance designers’ and business strategists’ vision and, consequently, the quality of their ideas, as they innovate products with long lifespans.

The motivators of, and the barriers to, CURA behaviors are presented in five tables (

Table 2. User-related motivators and barriers.

Factors			Independent User Circular Behaviors
			Care	Appreciate	Upgrade	Repurpose
User-related	Motivators	Positive attitude towards product longevity and the desire to achieve it through care activities
		Rebellion against brand policies that restrain users from performing some care activities on their own
		The user is environmentally conscious
		The user is confident in their ability to make the upgrade
		The user is economical
		User’s desire to become more self-reliant
		Necessity
		For self-expression
		User’s creativity
		User’s childhood experiences of making things
		A way to clear the clutter
		The user’s DIY spirit
	Barriers	The user lacks confidence in his or her ability to perform the care activity
		User’s concerns about the irreversibility of the care method
		User’s concerns about the outcome endurance and future damages
		User’s assumption that the product cannot be cared of
		User’s innovativeness
		Changes in user’s personal life
		Changes in user’s financial ability
		The user desires have changed due to technological progress and changes in fashion trends
		The user does not appreciate the product’s aging look
		The product has become aesthetically unappealing
		User’s concerns about the product’s reliability after the upgrade

,

Table 3. User-product-related motivators and barriers.

Factors			Independent User Circular Behaviors
			Care	Appreciate	Upgrade	Repurpose
User-product related	Motivators	The product is expensive
		The increase in the perceived aesthetic value of the product after the care activity
		The product is personalized to the user
		Perceived negative feelings from premature product discard
		The product is aesthetically appealing
		The product is associated with one of the user’s accomplishments
		The product represents the user’s lifestyle
		The symbolic value of the cared of product as a way of activism
		The product is used for social or joyful activities
		The product’s graceful aging which embodies the user-product history
		The product evokes some of the user’s memories
		The product is of high utility
		User’s emotional attachment to the product
	Barriers	The product is inexpensive, and the care cost is high
		The decrease in the perceived aesthetic value of the product after the care activity
		The product is unfashionable
		Lack of emotional attachment to the product
		The user finds no social value in the product
		The product design is inferior to competitive products
		The product does not provide the comfort of use the user desires
		Avoiding the interaction with a contaminated product

,

Table 4. User-process-related motivators and barriers.

Factors			Independent User Circular Behaviors
			Care	Appreciate	Upgrade	Repurpose
User-process-related	Motivators	User’s interest in using trendy methods or new technologies to take care of the product
		The perceived pleasure from performing the activity
		The activity does not require a lot of time
		The required effort is low
		The user has the required resources to perform the behavior
		To reduce stress and relax
		To learn something new
	Barriers	A sense of accomplishment from creating something original and personal
		The user does not have the time required
		The user does not have the required knowledge for the care activity
		The required effort is high
		The upgrade process is difficult to execute

,

Table 5. Product-related motivators and barriers.

Factors			Independent User Circular Behaviors
			Care	Appreciate	Upgrade	Repurpose
Product-related	Motivators	The product is of high reliability
		The product has personality
		The product is of high functionality
		The product is new
		The product material ages gracefully
		The product can be configured in various ways without needing extra parts
		The product is highly durable
		The product has a classic design
		The product is modular
		The product material is easy to work with
		The product is designed for disassembly
		The product is portable
		Product affordances
	Barriers	The product is of low quality
		The product is of low reliability
		The product is old
		The product quality is inferior to competitive products
		The upgrade results in a product of an inferior quality
		The product has sharp edges
		The product contains hazardous materials or components

and

Table 6. Situational motivators and barriers.

Factors			Independent User Circular Behaviors
			Care	Appreciate	Upgrade	Repurpose
Situational	Motivators	The product has a long-life guarantee or warranty
		Availability of care services
		Sharing and/or trading resources within the community is facilitated
		Social influences on the user
		Availability of a 3D printer to make the extra components
	Barriers	Inaccessibility to original spare parts, materials, and methods required to exhibit care behavior
		The stigma associated with repaired products
		Low cost of new products
		Promotion of frequent replacements by the selling company
		The product no longer complies with new legislations
		Media influence on the user
		Social influences on the user
		Advances in the market and the introduction of new, similar products with more features and better designs
		The product is no longer satisfactory symbolically
		lack of information about the product’s lifetime
		The stigma toward making objects from waste

). Each table contains factors belonging to a distinct category: Table 2: user-related factors; Table 3: user–product-related factors; Table 4: user–process-related factors; Table 5: product-related factors; Table 6: situational factors. The latter are factors that depend upon, or are the product of, the user’s circumstances but beyond all the aforementioned categories. Here, we would like to note that since the different tables of motivators and barriers are products of our review of the existing literature, they make it easier to identify the gaps. For instance, a glimpse at the table containing the user-related factors (Table 2), reveals the need for investigating the barriers to repurposing from users’ perspectives. Another note is that hyphenated category names (such as user–product-related) indicate that the motivators or, for that matter, the barriers relate to both components (the user and the product) or their interaction—not only to one of them.

5. Conclusions

This study set out to contribute to the movement toward Circular Economy in general, and particularly through building upon, and adding to, the current knowledge of user circular behaviors, and designing for them. The main objectives of the study were to identify independent user circular behaviors (ones that could be independently performed by the same product user) and their motivators and barriers. The study proposes a model for independent user circular behaviors: the CURA model. It includes four behaviors: care, upgrade, repurpose, and appreciate. The first three behaviors were extracted from the literature, whereas ‘appreciate’ is a concept we are introducing in this article. We define ‘appreciate’ as continuing to use a functioning, energy-efficient product as is. This behavior is basically a manifestation of resisting the product’s psychological obsolescence.

The CURA model succinctly illustrates the independent user circular behaviors. We believe that the model (and to some extent the acronym, CURA) can contribute to the promotion of circular behaviors, and it would boost their adoption. Moreover, as one reviewer of this paper wrote, “[the model] could provide scholars with interesting avenues for future research”. In addition to that, it should help designers and business strategists come up with innovative ideas to increase product circularity or innovate circular value propositions. Furthermore, the different categories of motivators and barriers should assist designers in developing products that stimulate independent user circular behaviors. All in all, the outcomes of this study should help with the conceptualization and actualization of more sustainable products and consumption patterns.

One limitation of this study is the small number of studies that took a user-perspective approach and employed qualitative, quantitative, or a mixed methods approach to identify the motivators and barriers to independent user circular behaviors. Clearly, there is a need for more studies in this area, especially ones that uncover the influencing factor of ‘upgrade’ behavior. Another opportunity for future studies is to investigate the ‘appreciate’ behavior introduced in this study. We anticipate that this concept will be useful and insightful for users, designers, researchers, and business strategists.