Some of both: https://jakeseliger.com/2012/10/20/why-you-should-become-a-nurse-or-physicians-assistant-instead-of-a-doctor-the-underrated-perils-of-medical-scho

Some of both: https://jakeseliger.com/2012/10/20/why-you-should-become-a-nurse-or-physicians-assistant-instead-of-a-doctor-the-underrated-perils-of-medical-school/ https://jakeseliger.com/2012/10/20/why-you-should-become-a-n.... But, from what I understand, the number of residencies is the big choke point.