There's not much to it
There's not too much to the animation and there was no real story or joke other then random guy with the mouth. Random isn't funny unless it's way out there or done right.
I don't care if it's short but there's gotta be something for me to enjoy like good writing, good joke, or good animation. Doesn't need all three but having one will make most people happy. This really doesn't have much of the three.