I seen videos where the chuck keys are left in the chuck, gloves worn while running the machine. Rags used on parts while running. many no nos.
Usually when the chuck key hits you after being left in you remember it. Chips or chuck jaws rough surface can and will grab gloves and suck you in, same with rags. Ive seen them pulling chips out of the way again a no no chips are hot and sharp they will snag and cut. Heavy chips will act just like a garrote.
Have a place for the chuck key ( other than the chuck) and always put it there. Some production machines had a tube with switch in the bottom it the key wasnt in it the machine wouldnt turn on. Dont wear gloves your hands will wash easier than being wrapped up around a part.same with rags. If for some reason I need to use emery the first few are not wrapped around but backed with a file. And last never use a file with out a handle. Youll be amazed how far a spinning chuck jaw can drive that tang into your wrist.