If by "just breaks" means "refuses to write code / gives up or reverts what it does" -- yes, I've experienced that.
Experiencing that repeatedly motivated me to use it as a reviewer (which another commenter noted), a role which it is (from my experience) very good at.
I basically use it to drive Claude Code, which will nuke the codebase with abandon.
I've had codex rm -rf the git repo it's working in while running in yolo mode. Twice, even! (Play with fire, you're gonna get burnt.)
I had it whip this up to try and avoid this, while still running it in yolo mode (which is still not recommended).
https://gist.github.com/fragmede/96f35225c29cf8790f10b1668b8...
I've seen it think for a long time and then just timeout or something? It just stops and nothing happens.