I follow a daily painting site called Daily Paintworks. Each week one of the painters from the site issues a challenge, and two weeks ago it was to paint a subject over several times in a small format taking no more than 10 minutes each. I just entered mine and it is on page 1 near the beginning of the paintings.
Ten minutes is not very long!!! No time to fuss or adjust, just get it down. One of the painters is Carol Marine, whose work I admire. I'm paraphrasing Carol here...."think in brushstrokes". Painting for me is so much more fun when it's about the brushstrokes (as well as light and shadow) as opposed to the object.