I don't have any experience in the field myself, but I have a couple friends who are involved with it. One is a nurse, the other is studying to become one. The first has been gone on strike to win better treatment and wages for nurses at the hospital she works at. She told me that nurses see the worst sides of people all the time, and are subject to a lot of stress. You have to be really dedicated to want to keep doing it, according to her.
My other friend who's a student says the same thing. She also gets mad at the other people in her major who are in it for the money. She has always wanted to be a nurse and says that it's her calling. She would do it for nothing, so when she hears other people say "Oh, I picked this for the money/easy job security," it pisses her off.
Working in the medical field is rough stuff. People dying or coming in injured in various ways, whether it be physically, mentally, or emotionally, people freaking out over their loved ones or pissed off at having to wait, and possibly working obscenely late? I could never do that, and I admire those who can.