With snapback actions you can quickly reverse an action that you did. For example, I create an action for this picture to enter the screen. Normally I'd have to add another action and move this picture out of the screen at the end of the clip is that I just add a snapback action and the reverse process of my previous action happens. I can also use it for sound. For example when I want to mute a part of the clip or lower my volume for it. I can quickly add a snapback action to undo in another part of the clip what I did in the first part