This is actually an interesting paradox to be in, and one that Linus Torvalds recently commented on. His focus, like Guido’s, is the user and even fixing a bug can break the user.
That's how you get an inconsistent mess that never evolves. There's something called semver, increase the version number and do the fix / refactors / radical redesign / whatever. People will see that you've went from version 1.0 to 87.3 in one year and they may choose not to use your thing because you're moving too fast for them, but that's life...