There was a guy in my research group who was easily the stupidest person I’d ever met. It was incredible.
Once I overheard him making a racket trying to pull some tubing off a really delicate bit of glass apparatus. I stopped him, explained that you need to cut the tubing off or you’ll break it. He said ok. I went back to what I was doing.
Heard the same sound. Went over again and said, look, if you keep doing that you’ll break it. And the glass thing will shatter and you’ll cut your wrist or hand. Here, look, cut it like this with some scissors or a knife. He said ok. I went back to what I was doing.
Heard the same sound, followed by the sound of shattering glass and a man crying out in pain.