My wife is a physician, but not a surgeon.

Most of medicine is relatively routine. A surgeon's skill isn't so much in the 99% of cases, but the 1% that have adverse outcomes. More importantly, their skill comes in identifying the possibility of adverse outcomes and preventing them from ever happening.

Me and you could easily be taught to do a routine surgery, like an appendectomy. However, we wouldn't be able to identify if something requires more treatment or prevent a patient from dying if things don't go perfect.