I’m that type of person that enjoys working way too much. But as a founder I had unlimited vacation time, which I quickly realized lead to no one taking vacation. So now I say “ten days minimum vacation”, and if you are dragging your feet on taking time off, you’re getting your Gmail, GitHub, etc access cut off on Friday’s, weekends, and or Monday’s when you’ve been working hard.
Currently not a founder, but a senior employee - never mentioned to my CEO that was my policy, and it’s quite nice to have a boss that does the same and forces me into long weekends.