I learn something every time I talk to my son. I think that's one of the greatest things about being a Dad. When I teach him something I learn something myself. His drum teacher told him to open up and express himself next time. He relayed that idea to me and I proceeded to apply that to his running. I said "You don't know how fast you are yet, until you run to complete collapse (failure) you haven't gone as fast as you can".
I honestly thing that's true in every day life. If you can't push to failure then maybe you're not learning anything.
It's a good life...