Does confidence improve execution, or can it distort risk perception?

A trader who trusts their system may execute consistently, but excessive confidence after a winning streak can lead to overtrading or taking lower-quality setups.

On the other hand, a trader who doubts every entry may hesitate even when the setup meets all their rules.

Where do you draw the line between healthy confidence and overconfidence? Should confidence come from recent results or from a sufficiently tested process?