While searching through Wikipedia for errors, I came across information about a gym I used to go to. The information said something interesting that I had never heard of before. This was because the information was not true.
On the 24 Hour Fitness website, there are five types of clubs that are posted other than the sponsored clubs. Wikipedia somehow invented another "level" of club called the "Express" club. I searched the entire 24 Hour Fitness website, but found no mention of an Express club.
The first sentence on each print-out says how many club types there are to choose from, and undisputably the numbers differ. Personally, I would trust the 24 Hour Fitness website to be the supreme source of information for the club. This leaves the question, where did Wikipedia get its club information, up in the air.