why opt out of getting reviewed?

[SteveB]

Question asked, question answered.

Sandy x

To play Devils advocate there is also the option that the lady doesn't want to read comments left about her looks, sexual ability and or accommodation. Possibly they find it degrading

I think that is the two answers.
And can be a combination of both. If she is not particulary good at her job, the some of the comments will be certainly what she doesn't want to hear.
Further to Lucy's point, (a man thing) it is too easy both in face-to-face encounters and in reviews to say something that you think is unoffensive or even complimentary but that the girl finds offensive.

[Louth Dominatrixadmirerr]

Because a very considerable number of ladies just don't pass the mustard at all and need to do some sort of client quality control class