Everyone is bound to mess up from time to time. Read that again: everyone messes up, even those who are typically very precise in their activities.
What I'm trying to say here is that even the people who will potentially be tasked with saving your life are bound to make the occasional blunder in the course of their work.
Is it unsettling? Sure. But sometimes the truth is unsettling. This r/AskReddit thread isn't going to inspire much confidence in medical professionals.