The number of sales and the length of a product life cycle might be different for different products but they all share a general pattern of growth and decline. This cycle can be shown on a graph ...

It is withdrawn when it becomes unprofitable. The level of sales determines where a product is in its life cycle. This can be illustrated visually on a graph: The life cycle, and how long it takes ...

There is, furthermore, a persistent feeling that the life cycle concept adds luster and believability to the insistent claim in certain circles that marketing is close to being some sort of science.