Mid Sweden University

Knowledge about obsolescence and its possible causes is instrumental to extend product lifespans. Product obsolescence may be caused by both subjective perceptions as well as objective and measurable deterioration of functionality. In order to extend lifetimes by avoiding and reversing obsolescence, this study addresses the current knowledge gap on how functionality of products develops over time, using a case study on shell jackets for outdoor recreational activities. Functionality over time is compared in terms of user perceptions, ocular assessments, laboratory measurements and, in addition, price. Data were collected at beginning of use, secondhand resale and end-of-life. In addition to ocular assessments and laboratory measurements, a survey was used to collect data from users on e.g. perceived functionality, price and duration of use span. Linear representations of perceived functionality and price decline more rapidly (5-6% per year) than assessed and measured functionality (both around 3% per year). This could be explained by properties such as appearance, which are included and seemingly important to user perceptions and price, but which are not assessed nor measured. The perception of such properties as low seems to be a more relevant cause of obsolescence than inadequate performance. This points to, for instance, timeless design to avoid obsolescence. The finding that measured functionality remains relatively high over time is important since concern about performance is a key barrier to secondhand sales. Information policy, such as performance-labelling, could thus contribute to reversing obsolescence. Future research could test the robustness of these findings as well as their generalizability to other products.