Since I used to paint oils primarily it was sometimes needed to add finishing touches once a layer dried otherwise it got muddled. It’s much like mixing all colors together and you get a green-grey-brown look. For some instances it was obvious when I needed to set the base color aside to dry and other times it was optional. I don’t typically like to break my stride once I get going on a painting as you get in a certain mental zone to create. Some people call this ‘reworking the art’ and I think this is fine and typical for most artists. You do want to be a little careful though as you may be covering up something special. I’ll never forget one day when I was in studio painting away and my teacher became very upset at me. I was painting over something I thought wasn’t very good. He explained he was going to ask to trade me that painting for one of his paintings and he was a Fulbright Scholar. Then I was more mad at myself than he was mad at me. Huge lesson learned there. So be a little cautious on when to leave it alone and when to add finishing touches.