"You are your greatest opponent"

What does this statement actually mean?

The key to winning, is actually to be ready to lose. But that is so against our own nature.

When we are young, we are strong and rash, we think the world of ourselves, we don't think we will lose. We feel that we need to win to prove ourselves to the world, to show that world what we can do. We are thus obsessed with victory, and tell ourselves to avoid defeat at all costs.

As we age, having proved ourselves, we build up a reputation. Now, we become afraid of losing that reputation. We become afraid of losing.

Yet to win, we must be ready to lose. So in the end, it is this nature of ours that we must be able to overcome, before we can truly be ready to win. Only when we have overcame our own weakness (being afraid of losing), clearing the clouds of obsession, can we see the key to winning.