Because a great many health issues don’t really require a doctor to treat. Most of the time the advice is something along the lines of, “rest and if it doesn’t go away in a week or gets worse, see a doctor.” Or “eat better and exercise.”

I’m not going to spend time and money going to the doctor for something that’s easily treatable at home with OTC meds and supplies, but I might look it up to see best practices on how I should treat it and at what point a doctor should get involved. It’s also a waste of the doctor’s time that could be spent on a patient that actually needs to see them.