As Bruce Wayne's father says "So that we can learn to pick ourselves up."
It is a hard thing to do, perhaps the hardest thing. Coming back for something that really hurts you, really makes you doubt: very hard. But if you can do it, you will be stronger, simply because you know that you can. You will have done something that you will remember every time you get knocked down. I do not believe that suffering ennobles people. But surmounting it does. It opens up possibilities.
I recently read a blog post by a creative writer who fell on his face, was utterly incompetent in front of a group because he was not properly prepared. It almost crushed him, but he summoned up from somewhere the anger and spirit to "get back on the horse" and try again. As I wrote to him, I believe from the bottom of my heart that such moments are magnificent, they are triumphs of the human spirit and beautiful in the eyes of God. I do not wish you adversity, but I do wish you the strength to surmount it and a long and powerful memory of having done so.
Why do we fall? So that we learn how to pick ourselves up.