The Waterfall Lifecycle Model

The Waterfall Lifecycle Model is the straw man of lifecycle models. It was first described in 1970 by Wynn Royce as an example of a flawed process, but has since become the starting point for describing lifecycle models. In fact, many software developers use modified waterfall models.

The Waterfall model is a sequential process:

The advantages of the waterfall model are:

predictive

simple

a bug caught early is cheaper to fix that the same bug caught late

The disadvantages of the waterfall model are:

the waterfall model is more than predictive, it's clairvoyant!

high-risk integration comes late in the process