## 2 Literature Review
### CE and Electronic Product Consumers  
In the electronics industry, the CE philosophy is focused on product eco-design, reuse, repair, refurbishment, re-manufacture, and recycling to increase their useful lifetimes and recover the raw materials from their waste [12; 36]. Some companies have been open to considering value-added processes based on closing-loops and reusing EEE as a cascade for multiple applications and the new product fabrication. [PERSON] et al. [37] demonstrated that the eco-design of equipment is essential for closing cycles and reintroducing raw materials to the system. This process enables the disassembling of modular parts and components to recover materials to reinsert them into the process [39]. The consumer is the protagonist who can ensure the feasibility of a CE model in the electronics industry. For this reason, it was necessary to analyze the variety of angles, such as demographic and socio-economic features, length of EEE use, reasons to consider equipment obsolete, disposal modalities to extend the device's lifetime, obsolescence of equipment, repair, safe ways of recycling, and others [9; 12; 17]. The literature review from [PERSON] et al. [40] confirmed that if a user has the habit to change their device to a new model, he or she will either sell it, give it away, or deliver it to a recycler; in this way, the materials will re-enter the circular system. However, if the user throws it away or stores it, the materials will be lost and unavailable to the system. [PERSON] et al. [17] determined that 40% of Mexican consumers store end-of-life cell phones for less than a year, sell them, give them away, or dispose of them, while the remaining 60% wait longer to give them away or sell them in a second-hand market. Similarly, [PERSON] et al. [9] noted that desktop computers and printers in Mexico often decorate home offices but have not been used for several years. In Europe, second-hand electronic products are not attractive to consumers, based on the belief that this equipment is already damaged or that it will work only for a short time. Studies performed by [PERSON] et al. [41] and [PERSON] et al. [38] confirmed that the main reason for not buying second-hand electronic products is because consumers associate these products with previously damage and repair,  
Figure 1: The lifecycle of electrical and electronic equipment (EEE) in Mexico. _Source_: [PERSON] et al. [12]. low quality, and a short lifespan. On the other hand, [PERSON] et al. [41] confirmed that users agree to buy in second-hand markets from friends or acquaintances whereby they can personally check the electronic product's status and operation. The eco-design of modular electronic devices facilitates the repair of these products and reduces the cost of their components since users can change them independently. In Europe, legislation has been passed to promote the eco-design of products and the availability of repair manuals/tutorials to enable users to repair their own equipment [42]. When equipment breaks and cannot be repaired and formal repair service is very expensive, consumers prefer to store the equipment or throw it away [38]. In addition, there are also smartphone suppliers that are already performing a CE like \"Shift\" [43] and \"Fairphone\" [44]. However, even providing a CE product they still have the problem of having enough consumers. The website \"iFixit.com\" has generated repair manuals and diagnostic tools to help consumers repair the damage that does not require a specialized technician, such as changing a car battery or saving a wet cell phone [45]. Age, education, and socio-economic level are key aspects of a consumer behavior survey. They are related to awareness regarding end-of-life WEEE's possible environmental impacts [46; 47]. Some initiatives to promote e-waste recycling, such as ecological payments or environmental deposits, have been more widely accepted by professionals, academics, and people related to the environment.