I just want to say based on your story logic....
It's other way, people should criticize to improve....for instance if people had not commented as cross on his painting, he would have not gone to his master...and would have not learnt this lesson that criticizing is easy but improvement is difficult..
So I think criticizing is a kind of challenge, which asks you ...... Do u have something better than this?
Regards,
Rajveerjeet