What does bathtub curve mean?

bathtub curve meaning in Business Dictionary

A form of the hazard purpose used in reliability evaluating that catches three levels of failure rates which can be observed in some products. The bathtub bend captures an increased but reducing price of failure at the start of the product life time, considering manufacturing problems, a reduced failure price throughout a lot of the usable duration of the product, and an escalating failure rate toward the termination of the functional life time.