If you want confidence, stop aiming to avoid failure. Aim to recover fast. Take the hit, learn the lesson, adjust, repeat. The man who can bounce back becomes fearless over time, because he trusts his ability to rebuild even when things go wrong.
Being smart is not enough. You need to be angry and pissed or else you lose that edge. You become a condescending piece of shit that just looks down on everything. You stop trying to adapt and forget that half the game is people. Learn how to read people like a book and nothing will stop you. The more you focus on yourself the easier this is to achieve paradoxically. If you understand yourself to the point where your blind spots are expected points of failure; you can systematically architecture a workaround. You need to employ your intellect into social structure. Stop treating people as random. Most people are NPCs and completely predictable. When someone records as an error in your system, stop and learn what you have to learn. The consistency is what creates the rule. The consistency is what drives the improvement. This is how being smart benefits you. If you’re the best at what you do but socially retarded, you’re as dumb as they get.
Your standards will isolate you. Good. Greatness demands solitude. Mediocrity is a crowd sport, excellence is a lonely war. Every time you’re misunderstood, know this: the higher you climb, the fewer can breathe your air.