I am sure that you’re a good doctor, but to answer your question, yes, there are many doctors who operate negligently, to some extent. I had a long experience at one of the major hospitals in the US following drastic weight loss and months of pain. A major hospital did various tests, and ended up telling me I had “health anxiety”. It turned out that I was actually developing LADA, a form of type 1 diabetes. Since I had already been diagnosed with celiac and was having primarily digestive symptoms, the tests they did focused on the digestive tract and they never investigated other causes. I had to finally go into diabetic ketoacidosis before anyone figured it out.