What about that database you need to build first? What about that framework? What about that syntax-directed command compiler? Get over it!
All too often, projects go dark for a few months at the beginning while the programmers build some absolutely necessary bit of infrastructure. Usually the team really believes that it's necessary, and that it will make things go faster in the long run.
YAGNI: "You Aren't Gonna Need It." This slogan, one of XP's most famous and controversial, reminds us always to work on the story we have, not something we think we're going to need. Even if we know we're going to need it.
XP's planning ...