Life is full of choices, and Mark made his choice so who am I to criticize. I closed my laptop and drove out of SV at 42, leaving behind a CFO job at a large enterprise software company with lots of career upside. My choice was predicated on the recognition that the price one pays for this type of career success was not worth it, to me. But my values are not your values, so the important thing is to make a thoughtful, informed decision about how one wants to spend their short time here.