It says the source is Yelp and that it is the worst rated in each state. So if they are only taking into account bad reviews on Yelp, that leaves a lot of room for error. I can’t be bothered to go leave a bad review on Yelp every time I don’t like the food at a particular restaurant. Liking or disliking food is very subjective. I only post a bad review if there are safety issues (such as cleanliness, food not cooked thoroughly, etc.) or extremely rude employees.