Design life

A disposable camera is designed to withstand a short life, whilst an expensive single-lens reflex camera may be expected to have a design life measured in years or decades.

Some public transport vehicles come into this category, as do a number of artificial satellites and spacecraft.

In general, entry-level products—those at the lowest end of the price range fulfilling a certain specification—will tend to have shorter design lives than more expensive products fulfilling the same function, since there are savings to be made in using designs that are cheaper to implement, or, conversely, costs to be passed onto the customer in engineering to provide a safe margin leading to an increased working life.

Design life is related to but distinct from the concept of planned obsolescence.

Two classic examples here are digital cameras, which become genuinely obsolete as a result of the very rapid rate of technological advances, although still in perfect working order; and non-digital cameras, which are perceived as obsolete after a year or so as they are no longer "the latest design" although actually capable of years of useful service.