Don’t take score too soon. How often do I depend on feedback to stay motivated?

Some things I am being reminded of as painting, like: don’t take score too soon. I always do an underpainting and then paint up in layers. When I do that, it goes through some pretty scary stages, sometimes where I think I should scrap the whole project. I take a photo at every stage so I can see my progress. This also lets me see if I did a better version before and if I’ve goofed it up, I can use the better version as a reference to fix it.  I’m currently working on something that is a little small, so I am waiting for some art pens to arrive so I can do the face and fine details like the fingernails. I usually do the eyes first on a painting so that I can have somebody to look at and talk to me as I’m doing it. It’s a little disconcerting to just have a blank face staring back at me giving me no feedback as I paint. It makes me wonder how often do I depend on feedback to stay motivated?