A lot of artists do not THINK about what they are drawing, they simply do. "Make this scene a bit funny!", so they'll just draw the mouth three times bigger, have the character go cross-eyed, and maybe add a bunch of crease marks around the mouth or eyes. This is a problem when you only reference your friends artwork for ideas instead of watching your own face, observing others faces, studying actors, studying other cartoons, or looking at any reference outside of your insular circle group at all. These people all draw the same faces because a director told them to "be funny" when there are much better faces that sell the scene.