From The Association of Food Journalists’ Guidelines for Critics.
The problem with that maxim is that it singles out negative restaurant reviews, which are no different, economically, philosophically or socially, from positive restaurant reviews. There is only one category, and that category is called “reviews.” And so it goes that restaurant reviews will always affect people’s livelihoods, regardless of whether they happen to be overwhelmingly critical or disproportionately complimentary.
To say that negative reviews “especially” should be based on multiple visits, as opposed to positive reviews, is hogwash.
Excellent point of view on the touchy subject of negative reviews.