Design for excellence (DfX) comprises a broad family of product design methodologies aimed at addressing the often-competing requirements of multiple stakeholders throughout the product life cycle. Among the most pressing contemporary challenges in DfX is integrating environmental considerations into product design systematically and comprehensively. The circular economy (CE) is implemented through various R strategies (e.g., 3R: reduce, reuse, recycle), providing a normative framework intended to guide pro-environmental design decisions and life cycle thinking. This study conducts a systematic literature review focused on product development and its alignment with DfX methods in the context of circular economy practices (CEPs) to identify prevailing research trends and structural gaps in this area. Both quantitative and qualitative analyses of the literature are performed and interpreted through the lens of the circular economy butterfly diagram proposed by the Ellen MacArthur Foundation. The results reveal a pronounced asymmetry in the distribution of CE practices within product design research. Recycling and remanufacturing dominate the literature despite being positioned in the CE framework as less desirable than resource-preserving strategies such as reuse, repair, and life extension. This imbalance suggests that current research and design practices remain largely anchored in end-of-life (EoL) and resource-intensive solutions rather than prioritizing strategies that slow material and product flows. These findings highlight a critical need to intensify research on product circularity at the design stage, with greater emphasis on life-extension-oriented strategies and their integration within DfX methodologies and practices. The study provides a structured foundation for future research on circular product design and contributes to ongoing discussions on aligning design practice more closely with the fundamental principles of the circular economy.
Bielecki et al. (Wed,) studied this question.