It was one of the phlebotomists (person who draws blood) at the hospital I worked at.
It was her first day going off on her own. She accidentally went to the wrong floor/area that morning. She drew many patients' blood that morning for the morning blood draws. The entire time she was there, she did not double check even a single patient's name at any point. They were all wrong. All were mislabeled. All patients had to be re-drawn and she was fired for gross negligence.
Things happen and I've seen things get mislabeled many tines before. It's not good obviously. But if you do it once and no one ended up getting hurt, you just get reprimanded and move on. You generally don't get fired for a one off. But never before or after have I seen that level of mislabeling.
My assumption would be that the training would put a huge weight on precisely that.
I really don't think they'd spend all that time just learning how to mechanically draw blood and not have entire courses and exams on patient safety, record keeping etc.