And the fewer opportunities you take advantage of, the fewer there will be. Imagine going to visit a friend. And he'll probably ask you a third time. If you refuse his offer three times, chances are he won't offer you a drink again that day. You've convinced him that you don't want one.
Life is the same way.
When good things come your way, and you ignore them repeatedly, soon they just stop coming at all. You've convinced the world that you don't want what it has to offer. Better to be prepared, because each opportunity you're able to seize will lead to countless other possibilities. Winners train for months and years before the actual competition. The winning is really in the preparation, not in the race itself.