The worst critic there could ever be is yourself it's human nature to compare your works and talents against others and it only holds you back no one can be you and if you learn to accept yourself you'll see you're just as good as anyone else
Some people do it professionally though and it does come in handy when people are like trying to figure out if it is: Good, Bad, or even Healthy. I'm not trying to become a Critic nor do I want to be but eh.