Working 40 hours per week is not being lazy: is balancing work & real life, keeping them separate and have both of them.

We work to live, we don't live to work.

What Elon Musk does is not "work": for him is an hobby and you can put how many hours you want in an hobby, but I don't believe for one second that his employees enjoy putting 100 hours WORKING hours and live an healthy and happy life