People don't understand why a plain "hard" leather saddle might be more comfortable to sit for hours on than a cushy foam saddle.
Here's the only way I can try to describe why:
If you were to take a couple of balls of dense foam rubber about the size of large eggs, and place them exactly under each sit bone, and then sit on those foam eggs on a chair for an hour, you would be in agony. If you removed those foam eggs and just sat on a smooth wooden chair whose seat was carved to the same shape as your butt, you would be perfectly comfortable sitting for an hour.