This came up in conversation the other day and it seems like a good way to introduce EmbraceChange to managers. I don't have my copy of Kent Beck's book (loaned it to a friend in the name of XpEvangelism :-). So I can't check to see if I'm just remembering something from there. But if I'm not, I hope this helps:
"ExtremeProgramming is a software development discipline that meets the challenge of delivering excellent software on time by raising simple, commonly accepted practices to extremes.
"Software development is about building a model of something in the real world (specifically a model of the information associated with something, so we can automate it and otherwise improve how we handle it). The real world is vast and complex, ever-changing on both the micro and macro level, at speeds both fast and slow. Our understanding of the real world is also ever-changing. By the time a software development project is complete it's usually inaccurate, or irrelevant. Or both.
"Traditional development methodologies try to prevent change problems by making sure we know all the answers up front, or by avoiding change, or by controlling change, or at least by documenting change (so you know who to blame!). In the pursuit of this impossible dream, traditional methodologies slow the process down and impose additional overhead, making the original problem that much worse. ExtremeProgramming is a methodology that recognizes that change is inevitable and beyond our control. ExtremeProgramming embraces change by discarding the high-overhead methodologies on the one hand, and on the other taking simple, well-defined, accepted practices and technologies that most experts will agree are worthwhile, and taking them to extremes.
"Testing (aka ContinuousIntegrationRelentlessTesting) is the simplest example of an extreme that I can think of to illustrate this approach. Everybody accepts that testing is good, but nobody does enough of it. ExtremeProgramming posits that testing should be the foundation that all the rest of XP relies on. If you have comprehensive UnitTests that you can and do run every twenty minutes - every time you make a significant change - you can have the courage to fearlessly EmbraceChange, because your tests will RealityCheck you as soon as you go astray."