Jacques-Alain Miller says in The Experience of the Real in Psychoanalysis:
It has been for many years now that health insurance companies have enforced a standard called “managed care” (soins organisés). Under such an organization controlling reimbursements, psychoanalytic treatment cannot be validated. Likewise the mandate of the health industry leads irresistibly the suffering subject away from psychoanalysis.
Miller's point here is that American insurance companies don't accept psychoanalysis as a "validated" treatment because psychoanalysis is not something that claims to cure a patient of something that is wrong with them. In addition to that, psychoanalysis never claims that by X time, a person will see results or they can have their money back.
(A bit more on this: psychoanalysis sees each and every experience of psychoanalysis as a one-off, as something that is for that one person alone, that can't be replicated. What works for one person going through a messy divorce/breakup might make another person's situation worse... Every person and every situation is unique! I see this as one of the great strengths of psychoanalysis.)
The insurance companies say, "Why would we offer to pay you for something you don't guarantee will cure, fix, or make the patient behave better than they do now?"
I find that lots of people (who have not tried psychoanalysis) have this same attitude. When I'm asked why someone would pay for psychoanalysis if it does not promise a cure, I say that a "cure" (I make air quotes with my fingers) might happen, but it probably won't be what a person expects it will be.
Sometimes, this leads to more of a discussion of the aims of psychoanalysis, but not all the time.