What makes us successful is how we deal with failure, mistakes, and let-downs. If we never failed, we would never learn, and so we must know that it is OK to try and to fail.
Think of all the great quotes about failure, like "'Tis better to have loved and lost than never to have loved at all" (Alfred Lord Tennyson). The successful ones that first had bankruptcy, the stories (and quotes) are endless. So why do we fear failure, when it only pushes us forward?