There are a number of reasons why a review might not be recommended. For example, the review may have been posted by a less established user, or it may seem like an unhelpful rant or rave. Some of these reviews are fakes (like the ones we see originating from the same computer) and some suggest a bias (like the ones written by a friend of the business owner), but many are real reviews from real customers who we just don't know much about and therefore can't recommend.
It's also important to note that because our recommendation software is automated, the Yelp Support team cannot manually override the software to recommend or not recommend a review. It applies the same objective rules to every business and treats reviews of advertisers and non-advertisers exactly the same.
For a detailed explanation of our recommendation software, take a minute to watch our video on the subject:
We hope to continually improve the recommendation software, and appreciate any feedback you may have.