People must accept that they are crap and no matter how good you are, there are countless things you can and should improve on.
Yesterday I broke a punching bag at the dojo with a low roundhouse kick, the torque made the chains that hold it up tear the loops they hang by. I was of course happy, sifu was proud but almost immediately he said "the kick can be better."
That same day I got punched in the face several times failing a parry drill. You literally roll with the punches, take pleasure in what you can accomplish and work on improving. I feel like if I had my old ego last year I would have gotten so pissed off at myself for failing the parry drill, that it would just put me in a foul mood the rest of the night. Dwelling on only the negative and not the positives.
Ego can kill progress and just hinder you.