>>100779015>When do you begin actually explaining how it looks bad?
Fine. First of all, let's get subjective enjoyment out of the way. Anyone can argue any piece of art looks "good" or is meaningful to him. So to objectively appraise art, we're forced to fall back on its technical merit.
To form criteria for good and bad animation, the nature and aims of the craft must be defined. "Animation" is a visual trick where successive still images are strung together in such a way that the viewer's brain is tricked into interpreting those shapes as moving forms with volume and depth. Therefore, the most technically successful animation is that which maintains said optical illusion, regardless of how true to life or realistically plausible the actions depicted on screen are. Smears further this aim by allowing shapes to move across the screen faster and more smoothly than the constraints of an animation's frame rate would otherwise allow. They're a tool developed for a specific purpose, though they can be used in other ways.
If good animation is all about fooling the viewer, then bad animation is the opposite: it fails to be "believable". A smear that lingers onscreen long enough for the naked eye to discern drastically distorted limbs, multiple eyes, etc. is not convincing. The illusion of form breaks down. The viewer sees the man behind the curtain, and the continuity of the viewing experience is disrupted. In that sense, a badly executed smear can be as distasteful as any technical error.
Of course, sometimes it's a legitimate "stylistic choice" to break the viewer's immersion. #NotAllSmears, since you seem worried about that. It can be used to add surreality or a cheeky meta reminder that yes, you're watching animation. But there's a difference of intent in those instances, and they have nothing to do with inexperienced or overworked animators relying on smears to fudge awkward perspective shots or when running out of time on a deadline.