A good plan violently executed now is better than a perfect plan executed next week.
I have studied the enemy all my life. I have read the memoirs of his generals and his leaders. I have even read his philosophers and listened to his music. I have studied in detail the account of every damned one of his battles. I know exactly how he will react under any given set of circumstances. And he hasn't the slightest idea of what I'm going to do. So when the time comes, I'm going to whip the hell out of him.
The test of success is not what you do when you are on top. Success is how high you bounce when you hit bottom.
Accept the challenges so that you can feel the exhilaration of victory.