There are a thousand excuses for every failure but never a good reason.

It is always possible to explain why something did not work out: bad luck, other people, poor timing, too little time. Those explanations may even be partly true. But an excuse is aimed at avoiding responsibility, while a reason helps you understand what to do differently, and the first kind is far more abundant than the second.

After a setback, try writing down every excuse that comes to mind. Then ask which of them, if any, points to something you could change. Those are the useful ones. The rest can be set aside without guilt, since their only job was to protect you.