My regular work is similar. Some days I don't work at all. At most, 3-4 hours. But I think this is because nothing I'm working on is particularly urgent. I'm well ahead of deadlines.

When I really get into my own side projects in code, the last of which I got heavily into about six months ago, I literally forget to eat or sleep and can go on 24-hour marathons - compulsively, without intending to, because I need to make something work. When there is a once-a-year crisis on my regular job, the same thing applies. It's actually beyond my control.

I wish I could harness that level of motivation to e.g. take on 3x as many clients and expand my studio, but just thinking about that makes me shut down. I feel lazy when I spend a whole day reading news sites or something... or even engaging in hobbies like music. But I don't want the burden of 3x as much work that I have to do. I earn low six figures and it seems enough.