If a business receives a lot of negative feedback, Facebook will share that information with the business and suggest ways to improve. If the feedback continues to be negative, Facebook will take action against the company, which includes reducing the number of ads the business is allowed to run. If the company still refuses to make improvements, it could lead to an outright ban on the business from Facebook.

In order to leave feedback about a business you've purchased a product from via Facebook, just go to your "Ads Activity" page. You can finds ads you've clicked on and leave a review about your experience.