Odds of Hanging On
Once you're in, you're in for good, unless you decide to leave or you do a really terrible job. Being a technician is a great starting point if you're trying to put yourself through med school to become something else, like a regular doctor. Many endoscopy techs use the position to fund their master's or Ph.D and then move on to greener pastures—pastures where the hours are just as crazy, but the paycheck is bigger.
You might also leave because you find that you don't like the work as much as you thought you would, which is, you know, totally cool. People change careers all the time.
What isn't cool is if you get fired for doing a terrible job. Not that we think you would, but just know that no hospital is so desperate for endoscopy technicians that they'll take on somebody who doesn't even know which end of the tube the camera is on.