The Worm Ouroboros, that forever eateth its own tail. That’s my development cycle.
I spent a year and a half, maybe even two years, building Exon as a procedurally-generated dungeon crawler. Over that time I rewrote the level generator at least six times, edging ever closer to a system that would actually make nice playable levels and not be insane to extend and tweak.
Then I decided it was time to finally attempt natural cave levels to break up the bunkers, and the whole thing fell apart again. Feeling that the near-constant rewrites of the level generator suggested a more fundamental problem with my approach, I have decided to change direction.