Sustainable product design (SPD) is a critical approach for mitigating environmental impacts and promoting socioeconomic welfare. This paper explores stakeholder behavior patterns throughout the life cycle of sustainable design, emphasizing their role in shaping product sustainability. Combining natural and cognitive resources within design methodologies elevates SPD beyond mere functionality, ensuring environmental stewardship and user satisfaction. Leveraging the TASKS framework illuminates stakeholder behavior complexities, optimizing cognitive resources for sustainable outcomes. Addressing implementation barriers and leveraging facilitators unlock the driving force behind stakeholder engagement, fostering active participation in sustainable design practices. The study envisions a future where informed stakeholder behaviors inherently promote sustainability, emphasizing the pivotal role of stakeholder behavior in achieving sustainable product design excellence. Through comprehensive analysis and strategic interventions, this research seeks to bridge the gap between sustainability objectives and practical implementation in product design, ultimately fostering a more sustainable future.