This is not true. Even if it is your project. For a regular person without all the paid support systems (maids, cooks, etc), burn out is inevitable. You can do

This is not true. Even if it is your project. For a regular person without all the paid support systems (maids, cooks, etc), burn out is inevitable. You can do it for a while, but its not a sustainable situation. It is also likely that recovery from burnout will take longer and reduce your efficacy much more than was gained from overworking in the first place.