I never felt it was because of ego; rather that I have high standards that I wish to maintain. I don’t think I come across as “whiny” about them and am generally pretty accommodating in trying to help people attain them. If I can pass on good (imo) habits, then all the better, but one only has so much time and patience. Reading this makes me feel remorseful; that maybe others don’t see me as a helpful or approachable colleague, despite my intentions.
It’s definitely possible to be both humble and demanding; I’ve known many people like this (they’re often senior academics, but that may be a self-selected sample). What’s their secret?