I quit high school, wasn't learning anything there, and joined the military to get out of my podunk nowhere backwater town which was only on the aussie map because it famously killed 15 back packers in a fire.
Went on to become a combat systems electronics engineer, an x-ray engineer and now I'm a bio-medical engineer fixing and installing hospital equipment around Australia.
Still no degrees, although I've had plenty of troops serving under me who had, and I've developed a firm belief that a university education is no substitute for real work experience. Some of us can pull it off, but not everyone can.
I guess its a variation of nurture vs nature.