Defeat never comes to any man until he admits it. – Josephus Daniels
. . . when you give up.
When you stop learning and trying.
When you decide that (the illusion of) safety and stagnation is better than intelligent risks and action.
Losing is not defeat.
“Failure” is not defeat.
Not-getting-what-you-want is not defeat.
Just keep going.
Learn from what happens.
That’s how you win regardless of the “score.”