You’re probably better off not even thinking in terms like failure and success. Rather, think like a scientist. Life is an experiment and there are only results.
The thing about pain is it demands to be felt. Somebody will feel it. If you don’t feel your own pain, it doesn’t go away, you just pass it on to the people around you.
You gain strength, courage, and confidence by every experience in which you really stop to look fear in the face. You must do the thing you think you cannot do.