Exercises are easy for me to finish.
Drawing Full Stop has been an exercise. I draw each chapter over the course of a week. I focus on drawing a line rather than on the kind of line I've drawn. While I still think about the quality of lines I've just made I don't let myself redraw them. What gets drawn is drawn.
For this reason the first chapter is a bit of a mess. But it's also the reason the second is much better than the first. And I think it's also why the third feels like the most finished things I've made.