I think part of it is that games (like films, novels, albums, etc) are intense, grueling creative efforts. I think many young dev teams go in pretty naive and strike gold, and assume it was hard because it was new. Then they make another and realize, nope it’s just hard every time. I think it would be very difficult to sign on to each new project after years of 70 hour weeks. What’s the point of success if you can’t enjoy your time after?