When challenged, focus on “getting better” — not doing well or looking good.

Get-better goals increase motivation, make tasks more interesting and replenish energy. This effect even carries over to subsequent tasks.

Via Nine Things Successful People Do Differently:

Get-better goals, on the other hand, are practically bulletproof. When we think about what we are doing in terms of learning and mastering, accepting that we may make some mistakes along the way, we stay motivated despite the setbacks that might occur… The amazing thing was that the people who were pursuing get-better goals (i.e., who saw the test as an opportunity to learn a new problem-solving skill) were completely unaffected by any of our dirty tricks. No matter how hard we made it, these participants stayed motivated and did well.