My own son wanted to to "do his own thing" for a while after high school, though with full intention of one day getting to college for an actual degree. I think he just wasn't sure "what he wanted to be when he grew up." He did some building for a while in other states, and decided that while it was interesting, it would be more interesting if he was a boss instead of a grunt.
He's always had a real knack for math and love of science, so he decided on electrical engineering, and he's doing really well so far.
He's a really exceptional case in a lot of ways; an only child (as I am, and as my husband was till he was 11 and his parents adopted a little girl), off-the-charts intelligent, and I've always talked to him and treated him like he has a brain in his head, rather than treating him like a small retarded person as so many seem to treat their children -- for example: I told him when he was 6 or 7 that no one could MAKE him behave himself in school and act right and do his work, that he had to choose whether he wanted to be rewarded for good behavior and good grades, or punished for naughtiness and bad grades -- the ball was in HIS court, for him to choose. He really got it. He did have a little trouble with grades, mainly with not wanting to do the busywork that constitutes "learning" in public school, but in his entire public school career, I had to visit the school for his behavior exactly ONCE -- otherwise, he was damn near a "model child" -- sure, he got silly and overwrought sometimes, but that's a kid for you; if he was more energetic or more vocal than I felt like dealing with or listening to, I told him to go do that in his room, and come on back out when he felt more sociable. That worked too.
Mainly, I treated him like a person I respected, and he has mostly returned that courtesy to me and his dad.
He's not working right now, he's going to school full-time; he's driving our truck (sole vehicle), we're paying for all the gas and insurance, BUT, he's getting a small monthly amount of food stamps, which helps the family budget quite a bit, and he's on Kaiser Permanente's Bridge program, which gives him 2 yrs of free medical care. He's considerate of our needs when we really need the truck (for paydays mostly, and when either of us need med. checkups for our various conditions), he does errands for us when he's not in school, he does his own damn laundry!
For living at home as an unemployed adult student, he's doing very well. Trust me, we wouldn't have offered him this opportunity if he was one of those "behavior problems."
It really does depend on the kid, and the conditions.
Andria