If you have an excuse prepared, you will be tempted to fall back on it.Excuses have you looking out to the world to explain your failure, rather than revealing the weak points in yourself.
Cultivating your mental habits such that it feels bad to check whether or not your failure will have an excuse. Refuse to have excuses. Refuse to cover your failures. Only then, without expected social protection, do you really start trying to figure out how to win.
You don’t need to win every time — but you do need to learn every time.