Let’s say you go to your doctor with a problem and she tells you that you can’t work because you’ve got a serious, long term disability. Most people would probably take their doctor’s advice as clear medical evidence that they are disabled and should be able to receive benefits.
Unfortunately, insurers don’t see it that way. If all your doctor does is examine you and the writes up a statement saying you’re not able to return to work due to your disability, insurance companies are liable to refuse, suspend, or terminate benefits. This is true even if they’ve been covering you for short term benefits, acknowledging that there is definitely a problem.