Most markets fail here. I can't even make good decisions about which electronics or appliances to buy, which restaurants to visit, which mechanic to use, and it's not for lack of research or unwillingness to pay. Advertising allows brands to build undeserved market reputation, and brands regularly sabotage their own legitimately established brand reputation for financialization.

I think it's particularly bad in medical decisions though because it's so much more advanced and cases are so varied it's difficult to compare doctor performance on different procedures. At least with products you generally get similar items each time so people can test multiple products in some scenario and a buyer can know what they buy should perform similarly.