It's also a natural weak point, because while almost all other vital points on the human body can be made more durable through training (i.e., strength training and hardening through impact training), that's nearly impossible on the neck in general, and the windpipe in particular. (Impact training on the back of the neck can develop extra bone to protect the spinal cord--you should see Mick Foley's spinal X-rays!--but it's almost impossible to do impact training on the throat without crushing the larynx and asphyxiating yourself. And strength training... well, how the heck are you gonna set up resistance/weightlifting to exercise your NECK? If you find out, a lot of race car drivers would like to know, because neck strength is one of the limiting factors for them these days...)