Why do I feel hurt when someone improves my work?

Someone improves a thing you built, and instead of glad you feel judged, as if the better way is a comment on your way. That reaction is human, and it is worth being honest about, because it quietly punishes the exact people you want thinking hard. Try to see what actually happened. Your approach worked well enough that someone could stand on it and see further. That is not your idea being wrong. That is your idea being the floor someone else built on, which is how every good thing improves. The better way is not a verdict on you. It is progress you helped make possible. Next time it stings, say one true sentence out loud: that is better, nice work. Say it even while the sting is still there; the feeling will catch up to the words. Reward the person who improved things and you will get more of it. Punish them with your face and you will slowly teach a whole team to leave your work, and its flaws, untouched.