Calibration is a measurable skill and most people start badly calibrated, usually overconfident in the middle range. It improves with scoring, and only with scoring.
The method is unglamorous. Before a trade, write the probability you assign to hitting target before stop. Do this for a hundred trades, bucket them, and compare stated probability with realised frequency. The gap is your calibration error, and it is usually an education.
Calibration pays directly, because position size should track confidence. A trader who cannot tell a 55 percent setup from an 80 percent one has no basis for varying size, and varying it anyway is just mood expressed in contracts.
Related: overconfidence, luck-vs-skill, behaviour-journal, conviction-vs-certainty