When your characters aren't stumbling around the screen they are floating in mid-air or stuck halfway through a wall thanks to the terrible collision detection.

It removes awkward collision detection, where rogue limbs harmlessly pass through opponents.

They are prone to getting stuck, sometimes irretrievably, on objects in the environment owing to a lack of adequate collision detection.

This stage may, for example, contain collision detection, speed-up techniques, animations, force feedback, etc.

This yields collision detection systems which operate in near-constant time.