It's important to distinguish between times we lose and played correctly, versus times we lose and made a mistake.
AA vs KK pre-flop: We still lose ~ 20% of the time. We won long-term EV and shouldn't worry because there's nothing we could do different.
If you make a mistake, it's often going to be taking the hand too far post-flop with deep stacks. For example:
We raise pre-flop with As Ac and get three callers.
Flop: 7h 6h 5h
Action: First player bets, second player calls, third player raises. This is a clear fold; if we put any more money in the pot, we are making a mistake (unless stacks are very short!)
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