A friend told me he didn't like swimming because every time he got to the wall he felt like he had an option to continue or not.

Contrary to running where you are miles away from home, the only choice is to continue on back home.

I wish he had never said that to me because swimming at 8,400 feet is no kind of easy on the lungs and in barely heated water I didn't even need to be at the wall to question continuing...