Forcing someone to punch a clock is definitely misguided. But work hours are a useful proxy for effort spent, provided you have good estimation of your pace. And being in the office not only puts you in a “work” frame of mind, but also promotes serendipitous sharing with your coworkers—swapping productivity tips, planning features, explaining systems.

So even in a quite results-oriented workplace, with almost total freedom over my hours, I still often choose to go into the office for about six hours a day.