Sometimes when I'm lifting weights I get to a point during a set where it seems like I should stop. Something wants me to stop, telling me that I'm tired. It seems like a good idea for half a second, until I remember something that I read somewhere about a month ago. It went something like this: "You're already tired and in pain, so why not finish what you came to do and get a reward for it?"
I have used this logic to power through some sets and improve the quality of my workouts.
I then wonder why we ever even have to stop at all. Why do we have physical limits? Can our mind power us through remarkable physical achievements? I'm sure that our nervous system has something to do with this, telling our mind to stop in order to avoid injury. Finding a balance between excess and injury then becomes the ideal to maximize every workout. That's something no personal trainer can do for us, it's something you have to understand yourself.
Can the quote I use be used in other areas? Sure it can. When you're doing a necessary activity that you don't enjoy doing, consider this statement and see if it works for you.