Task performance over time

Have you ever done some task over and over only to find that you were doing worse the more you did it straight?  I think this might be something that happens to a lot of people.  Of course, I don't have much support for that statement, but I don't have much to go against it either.  At any rate, it's something that happens to me sometimes.

This is how I feel I perform when I do the same thing over and over:

It's something I'm interested in for the purpose of doing things like improving game records, but it might apply to a lot of different situations.