Spending all the time on implementing new features is tempting. Experience teaches that a sizable amount of time has to be used for refactoring the code (delete cruft, rewrite code before even I struggle to understand the original intentions). That's well understood, since that's what makes code different from a quick hack.

However, the same applies to docs: they often start their life as snippets of informations on a scratch pad during a hacking session. Later, at least half of the information is no longer true, or incomprehensible even to the author. Note to self: don't underestimate the time necessary for refactoring the docs ;-)

This said, the docs in the GitHub Wiki got some love. It's never enough, I know.