I pushed a bug to production in my second week. My lead's reaction stuck with me.

Took down a checkout flow for about twenty minutes because I didn't understand a caching layer I'd never touched. I was already writing my apology-slash-resignation in my head. My lead just said, "okay, now you're the person who understands that caching layer — write up what happened so nobody repeats it." No blame, no lecture. First time a mistake felt like a deposit instead of a debt. I still sweat every deploy though.