"a cognitive bias that causes people to overestimate their positive qualities and abilities and to underestimate their negative qualities, relative to others."You've likely encountered it often as well: perhaps its the stat that 80% of all drivers think they're above average, perhaps it was in poll data where most people expect their peers to be worse off than their parents, but expect to do better than their own.
The bias is important to recognize - on an average its likely you're not as that much better than everyone else at something as you think you are. But on the other hand, unless you believe that you are (or will be) better than everyone else its hard to actually be better than everyone else.
So recognize the effect, but sometimes recognize that the belief is necessary.