Editing Service life (section)

== Product strategy ==
{{main|Product lifecycle management}}
[[Manufacturers]] will commit to very conservative service life, usually 2 to 5 years for most commercial and consumer products (for example [[computer]] [[peripheral]]s and [[electronic component|components]]). However, for large and expensive [[durable good]]s, the items are not [[consumable]], and service lives and maintenance activity will factor large in the service life. Again, an airliner might have a mission time of 11 hours, a predicted active MTBF of 10,000 hours without maintenance (or 15,000 hours with maintenance), reliability of .99999, and a service life of 40 years.

The most common model for item lifetime is the [[bathtub curve]], a plot of the varying [[failure rate]] as a function of time. During early life, the bathtub shows increased failures, usually witnessed during [[product development]]. The middle portion of the bathtub, or 'useful life', is a slightly inclined, nearly [[exponential distribution|constant failure rate]] period where the consumer enjoys the benefit conferred by the product. As time increases further, the curve reaches a period of increasing failures, modeling the product's wear-out phase.

For an individual product, the component parts may each have independent service lives, resulting in several bathtub curves. For instance, a tire will have a service life partitioning related to the [[retread|tread]] and the casing.