I'm curious.
Being a quitter means you can make a choice.
You can be a loser without being a quitter, but if you quit, you will always be a loser. One is a simple choice, the other is about circumstance.
Think about this:
If AE quit, he didn't need to have his locker cleaned out to make that decision. Maybe he was already going to, and the coach pushed him over. However, AE could have easily gone back up to the coach and said "Look, Coach, someone cleaned out my locker, but I don't want to quit. Look me straight in the eye and tell me that you don't want me on this team. I want to fight for that position, where are my uniforms?"
Remember, it's about choice. And some choices are more clear cut than others, and sometimes, they aren't as obvious.
I'm not sure that AE wanted to leave, but I'm not sure he was given much of choice. It could have just been a test. I'll take ScubaSteve's premise by saying that we don't know everything that went on, and certainly, this story is not over. But to call a kid a quitter may not be accurate at all. Jeffrey Martin presents the story as it appears to him. That doesn't mean he'll hear every side, and that doesn't mean a story isn't a story simply because one side has been reported. A fan has every right to evaluate what he/she reads to form their own opinion.