Why can't I let go of the deal I should have caught?

You built the skill to see what others miss. That skill did its work — it saw. Then something went wrong anyway: a partner lied, a market turned, someone above you chose differently. And you took the loss into yourself as if you had failed, instead of as the world doing what the world does. There's a specific deal you're thinking of right now. The numbers were clean but the man wasn't, or the timing was wrong and you knew it and said nothing. You've replayed it more times than it deserves. You are grading your past self on information your present self collected afterward. That isn't judgment. That's just unfair. Here is what's actually happening: you've made yourself the last line of defense against every bad outcome, so every bad outcome becomes a verdict on you. It is not. You examined what was in front of you with the skill you had that day. The rest was never yours to control.