It's one thing to know you're wrong. But another to know how wrong.
If you like beating yourself up, try backgammon.
It's a game for hustlers, played by mathematicians.
A skill that's hard to improve by trial and error.
The fixed number of choices make it possible to calculate the theoretically perfect next move. Grandmasters are measured on this Error Rate, their ability to make these choices precisely; more errors mean less mastery.
But mastery is only part of it.
Each turn also begins with a dice roll, letting in a little randomness.
Meaning a beginner could lay waste to a grandmaster.
Or a grandmaster might just get lucky.
Winning doesn't necessarily mean you're better. Maybe you just had luck on your side.
To truly master it, the right decisions are more important than outright victory.
So instead of winning the game, you have to raise your game.
You might play perfectly, and still lose. But that's life.
With huge thanks to @alecbarr90