Plus it's not the easiest thing in the world to kill someone - especially for the first time. My mate went to Iraq and the first time he had to kill someone it nearly did his head in. He had all the training and was top of his rank but the moment of actually ending a person's life was huge. Didn't help that the guy was only a few feet away from him as well.
Don't forget you must be able to take orders no matter what - that in itself can be a hard thing to do.
As for me, well I'm still a kid trapped in a grown-up's body. All my growing up time was kinda taken from me at a young age so I have no idea
But I would have loved to stay in my band and done more gigs, made more albums etc.
If I ever do grow up I think I'd like to be the first village idiot in space...don't know why...