Trading rewards a posture most people find unnatural
Almost every other skill rewards certainty. You study, you become confident, you act. Trading inverts that: the correct posture is confident about the process and completely uncertain about the outcome.
Holding both at once is genuinely difficult, and it is what "beginner's mind" means here — not naivety, but the refusal to be sure about something unknowable.
Thinking in probabilities
Any single trade has an unknowable outcome. That is not a limitation of your analysis; it is a property of the market. Enough participants with enough capital can move price against the best reasoning you will ever produce.
What you can know is the distribution. If your setup wins 45% of the time at 1:2, then over enough trades the arithmetic pays. Within any ten trades, anything can happen.
This has a direct consequence most traders resist: a loss is not evidence you were wrong. It is one draw from a distribution that contains losses by design. If your system loses 55% of the time, then 55% of the time it is *working exactly as intended* while you lose money.