Ask HN: Going to bed with *unsolved* problems in your head?

Now I've gone to bed with a problem in my head that I had some sense was solvable, no problem there and knock it out in the morning. What happens when you go to bed regularly with unsolved problems? Either you encounter a new problem regularly that you don't know how to solve by bedtime; or you have long standing unsolved problems? In my experience this is what causes burnout at the fundamental level. Protagonists/Antagonists have at it, revere me or shred me, its the internet I don't care.