if someone was to write a few fake reviews of some girls, especially the genuine independents and these girls don't flag them then other punters may begin to believe what this person posts/reviews. Eventually this person might write a fake review and this review will be taken as gospel because the reviewer hasn't been ratted.
Now if you are a normal person doing this then you are just a fucking lunatic, but lets say for example a PIMP or a disgruntled escort was to do this then it would be a very good method of muddying your competition.