Just a passing curiosity, but does anyone have any idea how physicians ever got their positions as authorities on medicine by royalty when their knowledge at the time was so superficial, and often just made up?

by Stigma_Storm

I've been binging a lot of history on old and ancient europe to help give me references to look on for building the lore and world of a fantasy story I'm trying to write. I want to make it as close to real historical human behavior as possible and establish fine mechanics about this worlds politics, class systems, infrastructure, technology, and even going as far as tieing magic to rules that compliment the fundamental laws of nature, chemistry, and physics.

One writing hurdle I've encountered is trying to understand how royalty appointed their advisors and why they keep them around even after failing spectacularly. In this case, particularly how royalty would appoint a royal physician when their knowledge was often wrong and often really dangerous and more harmful. Does anyone have any examples of how these figures took and maintained their positions? I'm certain many self appointed "doctors" met their end for the recommendation of bogus medicines or advice by an angry monarch or their surviving family and supporting factions.

In this case, particularly how royalty would appoint a royal physician when their knowledge was often wrong and often really dangerous and more harmful.

I'm afraid you're starting from a false premise here. Whilst modern medicine is most definitely more efficacious than medieval medicine, that is not to say that medieval medicine was 'bogus'. These previous posts may help shed some light on the matter:

First, since you touch on the matter of why Medieval people trusted doctors and physicians, I'd recommend this post by u/pettylarceny (the actual post is linked in that thread, but there are pertinent comments in the newer thread).
Second, on the matter of treatments, here's a non-exhaustive list of Stuff That Worked from u/BedsideRounds, and the matter of Bald's Leechbook from the 9th Century, as explained by u/BRIStoneman.

Also, u/BRIStoneman does link to it in their earlier answer, but I'd just like to repeat: Anyone wanting to read Bald's Leechbook can do so, here in its digitised form.