Snippets of Agile History

"Evolution" is a technique for producing the appearance of stability.
A complex system will be most successful if it is implemented in small steps and if each step has a clear measure of successful achievement as well as a “retreat” possibility to a previous successful step upon failure.
You have the opportunity of receiving some feedback from the real world before throwing in all resources intended for a system, and you can correct possible design errors...

-- "Software Metric", Tom Gilb, 1976