The worse-than-average effect is a cognitive bias that causes people to underestimate their own achievements and capabilities in relation to others. this potentially self-handicapping bias seems to occur most when chances of success are perceived to be extremely rare such as unfamiliar tasks or athletic challenges such as learning to throw a 3 point shot in basketball while there is no consensus on why this occurs most people seem to have an aversion to differentiating themselves or bringing excessive attention to themselves.