Not everyday is going to be a winner.
It is inevitable that you will wake up some days and not feel yourself. You may be stressed, tired, or just overworked.
Underperforming is what makes each of us human. Failure heightens the sensation of success. Success eliminates prior failures.
Treat each day without bias or judgment and work as hard as you can. If it ends up not being one of those "winners," accept it and set tomorrow up to be fantastic.
It all balances out in the end.