I got this quote from some guy named Scott.  It suits me so I hope he doesn't mind if I borrow it!
To be a cyclist is to be a student of pain...  at cycling's core is pain, hard and bitter as the pit inside a juicy peach.  It doesn't matter if you're sprinting for an Olympic medal, a town sign, a trailhead, or the rest stop with the homemade brownies.  If you never confront pain, you're missing the essence of the sport.  Without pain, there is no adversity.  Without adversity, no challenge.  Without challenge, no improvement.  No improvement, no sense of accomplishment and no deep-down joy.  Might as well be playing 'tiddly-winks'.