You shouldn't laugh at people who are trying their best
Joe is a football coach, and a very weak man is trying out to play quarterback.
Joe wants to comment on the man's play.
Joe tells the man that he wishes that the other players were as fearless as him.
Joe tells jokes about the player's skill and starts laughing with the other coaches.
The man's confidence is greater, and he feels proud of himself.
The man's feelings are hurt, and he loses all of his confidence.