No, Yelp doesn't recommend every review from every user. We get millions of reviews from our users, and our job is to showcase the ones that best reflect the opinions of the Yelp community. These recommended reviews comprise about three quarters of the reviews we get. The remaining reviews are accessible from a link at the bottom of each business's page (and can still be seen on a user's profile page), but they don't factor into a business's overall star rating or review count.
This approach is very different from other sites that tend to feature every single negative rant and positive rave. We do our best to nurture a community of users who actively contribute reliable and useful content.
For a detailed explanation of our recommendation software, take a minute to watch our video on the subject: