This is an additional action that supports the main act. A secondary action is an integral part of animation as it adds interest and realism to the scene. It originates from immediate action, such as when someone’s arm moves backward after throwing something forward.
Secondary actions are helpful when animating something like a walk cycle where one leg will swing forward while the other steps backward, creating balance as you go along with your motion. Hence, not all weight falls onto just one side making things look less stiff than they would otherwise be without this addition.
How to create secondary action
To create a secondary action, the animator needs an image that illustrates the main idea. Then the secondary animation becomes a movement that happens depends upon the first image, an active motion. For example, when someone shakes their head, the primary action would be the head itself, and things such as hair or floppy hats are examples of secondary motions.
Where animators use secondary action
All animators use secondary action. It brings continuity to a story making it more relevant. Secondary action is another behaviour the character does which enlivens a scene and also reveals their personality. If done right, it can tell something about them or hint at why they are doing what they’re doing and add an element of subtext to storytelling. In short, animators use it for more than just creating filler scenes to make things interesting when telling stories.