Great feedback says 'I believe in you' and 'this can be better' at once

The soul of good feedback is managing to communicate two things simultaneously: 'I believe in you' and 'this can be done better.' That combination lets you transmit both confidence and high standards to the player. The fundamental rule that makes this possible is to always judge the action, never the person. When players feel the feedback is about what they did — not who they are — they can receive even demanding corrections without it damaging their sense of self or motivation.