I know that after an hour or so I'm much more able to tolerate pain and remember where I put things, two distinct advantages that have always kept me doing it.
Well, that and the fact that it's fun once you get the hang of it. You just never know where your brain is going to take you next.
...there was a surprisingly large group of practitioners who believed that a concentrated effort could levitate the pentagon. Though I didn't join them, I always wished them well.
Forty years later, I understand what they were doing.