To each their own, but I'm not paid to work 24 hours per day, and doing so would undoubtedly affect my outside-of-work relationships and interests.

My experience is that there is not a linear relationship between effort invested and output. It's a diminishing returns problem after 8-10 hours per day, so it's not even productive for me to spend all day and night churning on a work problem, even if I wanted to do that.