Sounds more like a lens problem than a self-concept problem. Like he is wise enough to know what he doesn't know, and passionate enough to want to fill himself in those areas. It also means he isn't trying to compare himself to his perception of others but only to his own internal measures. Without comparing himself relative to others, what does bad mean? I would move away from bad as a term. I could be misjudging it. Maybe you could say that people who say they are bad at something mean that it is an area they don't care to try and improve in?
