most doctors - like most mechanics - are the worst debuggers in humankind.
I once went to the UCSF er 2x in the same weekend for an issue. On day one, I was told to take some ibuprofen and drink water - nothing to worry about. I went home, knowing this was not a solution. Day two I returned to the ER because my situation had gotten 10x worse. The (new) doctor on day 2 said "we need to resolve this asap" and I was moved into a room where they gave me a throat-numbing breating apparatus and then shoved a massive spinal tap needle in my throat to drain 20ml of fluid from behind my tonsil. I happened to bump into the doctor from the previous day on my way out and gave him a nice tap on the shoulder saying, thanks for all the help, doc. UCSF tried to bill me 2x for this combined event, but I told them to get fucked due to the negligence on day one. The billing issue disappeared.
I had a Jeep that I took into the shop 2, 3, 4 times for a crazy issue. The radio, seat belt chime, and emergency flashers all become possessed at the same time. Using my turn signal would cause the radio to cut in and out. My seat belt kept saying it was disconnected. No one could fix it. What was the issue? A loose ground on the chassis that all of those different systems were sharing. https://www.wranglerforum.com/threads/2015-rubicon-with-elec...
These are just two examples from my life, but there are countless. I just do everything myself now, because I trust no one else.