A poor result is still a result, and results are what let you improve. Quitting mid-attempt protects you from the number but leaves you with no information, so the next attempt starts from the same blank place. Over time the people who finish badly and keep finishing pass the people who only complete the ones going well.

When something is clearly not your day, finish it anyway at whatever pace is honest. Write the number down without commentary. Next time you will have something to aim past, which is more than you had.