A failure is a man who has blundered but is not capable of cashing in on the experience.

Blundering is not the interesting part, since everyone does it and much of it is unavoidable. The real difference is between mistakes that get converted into something usable and mistakes that are merely suffered. Labelling a person a failure is a harsh way to make that point, and the useful version is gentler: what fails is a response, not a human being.

After the next thing that goes wrong, wait until the sting settles and write one sentence about what you now know. That sentence is the whole return on the experience, and it vanishes if it is never written.