Something that has bothered me for years is bad computer animation. My definition of bad is if it looks like vinyl plastic. Another definition of bad is characters that move in a zombie-like motion, and are devoid of subtle expressions. It used to be you only saw this sort of thing in videogame intro movies and cutscenes. Nowadays though with amazing new graphics engines like in Doom 3, you can see the plastic zombie humans directly in-game, real-time.

The problem is that the technology is not good enough to portray a realistic figure in motion. But you can get close. Unfortunately the closer you get without being there, the more unrealistic it becomes. When the image consists of 1000 polygons it is obviously somewhat abstracted so the viewer doesn't mind when it doesn't behave quite perfectly. However, when the model is 300,000 polygons and looks perfect while at rest very small differences between it and reality are much more obvious. If something looks correct but moves incorrectly then it actually comes across worse than a more abstracted figure would.

Primarily the problems with realistic models are as follows; Individual musculature is not tied to character movement. This means that the minor distortions and shape changes in the figure don't directly correspond to the motion. Texturing is another very common issue. Skin shading has subtle variations in it along with texture variation, and imperfections. Commonly characters are rendered with far too perfect skin, lacking these details. This makes them appear more like mannequins than anything else. Along with the texturing is the lighting. Skin doesn't reflect and absorb light in a uniform manner. Minor skin variations, tendons, hair, veins, and other things affect the light quality. Another problem is that animated models move too smoothly. Since they are usually built around a relatively simple skeletal framework, they achieve a fluidity of motion impossible for a creature made of flesh and blood to achieve. Animation should take into account the varying degrees of force, resistance, and friction in both gross and minor movements.

With the above mentioned limitations you end up with animated characters that move too perfectly and look hyper-realistic, lacking the flaws present in reality. This leads to a somewhat disconcerting realization that the characters are in fact not real, even though they appear so at first glance. Their realism works against them because the dichotomy between that and this realization makes the suspension of disbelief more difficult that it would be if the characters weren't so realistically represented. As an example I honestly think something like Virtua Fighter 2 works better than Virtua Fighter 4 due to its more abstracted characters. I don't know about you but too perfect characters that move in a puppet-like fashion kind of creeps me out.