He apparently has one. YOU. You've diagnosed him with a trait -lack of confidence-consistent with what psychologists call Generalized anxiety Disorder (GAD) Now exactly how you did this without interviewing him, giving him tests, etc is a wonderful attribute. I envy you. Of course if what your really saying is you "think" he might suffer from a lack of confidence then disregard this post.

No one knows-at least here-what if any anxiety he may or may not have.