hopefully you see friends along the way both in and out of the race, so yeah I think most people look forward to it. However, somewhere 14-16 miles in most people have to go into a grind. There were times I just kept going for the next telephone pole, all the while knowing there is still 5 miles left. At that point, it's no longer fun. I always found it easier if I could get behind a pony tail doing a figure 8. Somehow that mesmerized me.
When it's done, you have the memory and the accomplishment forever. Usually, you make some new friends along the way.