You speak like someone who probably hasn't spent a good chunk of their life as a patient. You are correct; the best doctors know the limit of their own knowledge and will respect a knowledgeable patient. I respect my top notch specialists more than anyone on the planet. But those are the best doctors. There are many more average and outright bad doctors, just like any other skilled profession. Some that can't keep their ego in check, some that just aren't very good at deconstructing a complex problem.