No, but they require nights and weekends, even if unofficially, and other infringements on your free time. When I’m not at work I have 0 work obligations. Work like crazy your first year and you can make just as much with 12-15 days off after you upgrade. Buddy of mine is a consultant and he’s gone 4 days a week and in the office on his fifth. Weekends aren’t truly free either.