“Our achievements speak for themselves. What we have to keep track of are our failures, discouragements, and doubts. We tend to forget the past difficulties, the many false starts, and the painful groping. We see our past achievements as the end result of a clean forward thrust, and our present difficulties as signs of failure and decay.”
If you gloss over your failures, you miss the chance to learn from them. Learning from failures is what makes them a necessary part of success.