Give yourself the opportunity to _______. A few months ago I read From Last to First by Charlie Spedding. It's about a guy that by many standards would be considered quite average, but he gave himself the opportunity to excel and he had a few really great moments because of that. Do the same for yourself.
Give yourself the opportunity to get an A, the opportunity to get the job you want, the opportunity to win whatever you are contesting. People seem to shut down and lower their expectations so soon in a process. It is fine to have low expectations, but don't let those low expectations limit your opportunities.
Maybe it is just me but I feel most people have a hard time conceptualizing more than a 10-20% improvement in any given area of life. Well, there are some things that are far more than 20% better than what you have now. What are the limits? What is possible? Only that which one has the opportunity to do.