Most of the other comments are basically saying this ("the pay is too low for too long for not enough reward").

Anecdotally: I'm teaching a course in "How To Be Successful In College" (not it's real name) at the US community college where I teach Computer Science. I've got more than 1 student who are going to get a credential for nursing because there's just no way they can spend 8-10 years in school to become a doctor.

Would they be good doctors? The question is moot because it's never gonna happen.