What this is

What this system is trying to produce: the change it is after, for whom, and over what time horizon. Goals point the system somewhere.

Why it matters

Without a goal you are only measuring activity against itself, PB for its own sake, and a system that promises more while delivering less deepens the disillusion it was meant to cure. The goal is the reference every other node gets tested against, which is why it belongs first even though experienced diagnosers often skip it.