Chapter 25. When You Shouldn't Try XP
The exact limits of XP aren't clear yet. But there are some absolute showstoppers that prevent XP from working—big teams, distrustful customers, technology that doesn't support graceful change.
There are practices in XP that are a good idea regardless of what you think about the whole picture. You should do them. Period. Testing is a good example. The Planning Game probably works, even if you spend more time on estimation and up-front design. However, as the 20–80 rule proposes, there is probably a huge difference between all of it and not all of it.
And all of XP, frankly, is not a story that can be told everywhere. XP is not a story that should be told everywhere. There are times and places and people and ...