Each time you judge yourself, you break your heart. — Kirpal Venanji
While there are times I do believe you need to keep a critical eye with your art (which in a sense is making a judgement about yourself, or rather the work you have done), I can also relate to this quote.
Please note how I phrased that in the parenthesis. When you are creating, it is very easy to think at first that you are judging yourself when you are checking over your art. but you aren’t. It is something you created. It is now separate from you. If a piece isn’t turning out as well as you hoped, it’s not that you are a bad artist. In fact, this is a good thing. It actually means you are growing as an artist and seek a higher level of craftsmanship. So don’t get all depressed (and break your heart) believing you’re no good. Rather, remember that it’s a sign of your learning. Go back and keep working on that piece until it is better. Keep the judgement on the work instead of yourself. That’s where it belongs.
As long as you can keep the separation between you and your work, you’ll keep pushing yourself to get better and better.