20. The Glass was not There
The back of the Brady house had massive glass sliding doors, which the family would often use to enter and exit. Whereas the front door of the house was on location, on a real house in the valley of Los Angeles, the rear side of the house existed only on a soundstage. Using them was a lot easier than going on location to the house in the valley or trying to reproduce that entrance on the soundstage. Keeping them glass free made them safer.