Comment by dgreensp

"Quality" here means the quality of your result. If you are learning to paint/sing/code, it means how good the painting/singing/code is. The advice is to not "worry" about the quality, in the sense that if you are not producing good quality output, that does not mean you are doing anything wrong. When you are just learning something, the output will not be good quality! You need to produce a lot of crap results, and that makes most people uncomfortable.

I can relate what you're saying to my experience taking singing lessons, though even there, I find that making progress is all about turning off the inner judge while you practice. All you need to practice something is a bit of intent and a bit of awareness; it's not important that you "worry" about the quality of what you are doing, per se.