I'm your average SV employee, not an industry-dominating CEO.

To me it's a matter of getting it done - no one is going to derail or disrupt your workout at 5:30 AM by calling you to see if you want to go get a drink last minute or by having to shuttle your kids around after school. Similarly, you're not going to be relying on your willpower at 8PM after a long, arduous day.

That's been the biggest benefit to me personally. The confidence (both in appearance and sense of accomplishment) and energy boost throughout the day is icing no the cake.