I think that self confidence help a lot such us you will be able to accept you faults and learn from it, even if the people still remember that you're a loser, you can't get your goals. However you're the only one who has the knowledge of his abilities.
In addition to this, you will have a strong personality.
More, If you have a project to do in front of the public, you need that confidence to present you project comfortably
