Critique of R.A.D. Methodology

A Brief History of Rapid Application Development.

Typical systems development lifecycles devised in the 1970s; such as the Waterfall method, which are still widely used today; are based upon a well-planned step-by-step approach. This inflexible sequence forces a user to “sign-off” after the completion of each stage before proceeding to the next one. The requirements and design are then “frozen” and the system is coded, tested, and implemented. Consequently using such conventional methods inevitably creates a long delay before any results are seen, and the development process sometimes takes so long that the customer’s business has fundamentally changed before the system is even ready for use.

As a response to this rigid series of one-way steps Boehm introduced the Spiral Model, a risk-driven approach that used process modeling and prototyping as a way of reducing risk.
Similarly, Gilb’s Evolutionary Life Cycle was based on an evolutionary prototyping rationale wher...