Continuity mistake: When Fred and Barney are driving home in Fred's car, the hole in the back of the car changes shape between shots.
Continuity mistake: When Wilma and Betty are watching "Shinrock" on the TV, the camera cuts to Pebbles and Bamm-Bamm and the rug they are sitting on is covered with building blocks. Later on, when the two are trying to dance the "Pterodactyl", the rug is completely clear.
Answer: The ratings had declined in its last few seasons, and the series was cancelled.
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