21. All Cast Members Have Their Hair Trimmed Every 5 Days For Continuity
A major issue on a show unfolding in approximately real-time is continuity: the wardrobe and make-up departments have to work overtime ensuring that everyone's clothing is consistent from episode to episode, and that hair remains the same length. A day in the show's time takes about 6 months to film, and so every long-term cast member on the series has to have their hair cut once every five days to ensure there aren't any embarrassing errors spotted by keen-eyed viewers. It makes sense, but on the other hand, it would be pretty hilarious to see characters' hair growing over the course of the episodes.