A Critical Discussion on Bath-tub Curve

The typical bathtub curve and its “standard”shape have been widely accepted as an engineering tool in reliability management and training. However, some recent researches reveal that the typical theory of ‘bathtub curve’is not so convincing in some situations. Therefore, a critical discussion is developed to research the bath-tub curve along three significant periods of bath-tub; i.e. infant mortality, useful life and wear-out. The discussion is not only focused on the performance at different period but trying to reveal some in-depth theoretical considerations and practical contradictions behind every specific distorted“bath-tub”. At last it concludes that the true meaning of bath-tub curve is on the business practice of the real world rather than any simplified models.