Hasn't happened to me but it is one of my biggest fears. Occasionally I read reviews of a provider that all of  her reviews say BBBJ except a couple that got CBJ and it wasn't of his choosing. That would be a self esteem crusher IMO.
I do wonder about the providers that almost all her reviews say CBJ but she looks so good and reviews are excellent other than the CBJ, I book anyway and she gives me BBBJ, and  tells me don't tell if I do a  review.  Most guys would see that as a ego booster. I see it as her looking at me, as one more gullible guy .
I don't write a review if she tells me not to let anyone know what we did. I would rather keep quiet than lie.
If I wasn't so cynical I would have a home full of Russian babes who want to visit me..