Indeed. But you also need the discipline to walk away. If you are going to do startup/work back to back, you must also be able to take a true break on the weekends, or else it's burnout city. You can go a long way on pure passion alone, but your body will check you are some point if you are abusing yourself.

+++ This is so important and one of the hardest things for me. I discover that when you schedule for leisure, you are less likely to feel guilty about taking a break.

Why no alcohol?