You know that special feeling when you're walking through your C codebase and suddenly realize you've been trampling all over memory you shouldn't have touched? Yeah, that's the one. Stepping in undefined behavior is like stepping in dog crap – you don't always notice it immediately, but once you do, the smell follows you everywhere. The worst part? You can't just wipe it off. Now you're debugging CSIDESCISSING HARD DATA CLAIMS, which is basically C's way of saying "congratulations, you've corrupted memory so badly that even your error messages are having a stroke." Segfaults, corrupted stacks, random crashes three functions away from where you actually screwed up – welcome to manual memory management, where the compiler trusts you completely and you absolutely should not be trusted.