A precise understanding of product obsolescence is fundamental for extending product lifetimes and promoting a circular economy. Previous studies have revealed that various factors affect product obsolescence other than failure. However, very few studies have quantitatively examined the relationships between these factors and product lifetime. Therefore, this study investigated the relationship between the lifetime of consumer appliances (digital cameras, microwaves, and PCs) and the reasons for their obsolescence based on a questionnaire survey to Japanese consumers. Device failure appeared to be the major reason for product obsolescence for all products. However, consumer demand for new functions or other new device characteristics was also a significant reason for product obsolescence for digital cameras, regardless of the duration of use, as well as for microwaves during the first three years of use. These results provide useful insights for designers and manufacturers aiming to extend product lifetimes.

准确了解产品报废是延长产品寿命和促进循环经济的基础。先前的研究表明，除故障外，还有多种因素会影响产品的过时。然而，很少有研究定量研究这些因素与产品寿命之间的关系。因此，本研究基于对日本消费者的问卷调查，调查了消费电器（数码相机、微波炉和个人电脑）的使用寿命与其过时原因之间的关系。设备故障似乎是所有产品过时的主要原因。然而，消费者对新功能或其他新设备特性的需求也是数码相机产品过时的重要原因，无论使用时间长短，以及在使用的前三年内的微波炉。这些结果为旨在延长产品寿命的设计人员和制造商提供了有用的见解。