"You're never as good as you think you are or bad as you think you are"
One day you're at the top, the next in the ditch. When competitions go poorly athletes tend to think the worst...I'm overtrained, or I need to train harder, how did this guy skate faster when my technique is way better than his? When things go well you feel pretty untouchable until the next day when your body decides to take the day off. The truth is, in sports where results depend on so many variables and subtle preparations that can each make a substantial difference, it's a safe bet to say that you're abilities lie somewhere in between your high's and low's.
But that's not to say you can't take those high's and ride them out as long as possible.