Stock footage
Stock footage refers to a sequence in film or television that can be frequently re-used. It is frequently used in animation to save the time and expense of having to re-draw sequences that are more or less assured to take place in every single episode.
In the context of Transformers, it applies to most of the series based off Japanese anime: Victory, Beast Wars II, Beast Wars Neo, Robots in Disguise, and the Unicron Trilogy. All of those series would frequently, almost ritualistically, showcase the same footage of characters transforming, combining, or deploying unique weapons. These sequences often feature the characters standing in front of a set background that may not match the setting of the actual events of that part of the episode; instead, the entire standard background may fade away and be replaced by streaking speedlines and flashes of color.
The dub for Transformers Cybertron poked fun at the practice, having characters narrate their stock-footage in a way that implied boredom or curiosity ("Why do we always go this way?").
