I remember talking to some Chinese cadets undergoing a 737 type rating in NZ many years ago. I asked them how they got into flying in the first place.
They said they were all attending University in China for various disciplines (optometry, civil engineering, medicine, etc) when in walked the military and all students were tested for flight crew medicals. Those that passed were streamed into either military pilot flying or airline pilot.
One candidate failed the medical because he had buck teeth
