Cats have much better long-range vision than short-range. Long range they are probably better than you think. Short of about a foot they don't really focus at a

Cats have much better long-range vision than short-range. Long range they are probably better than you think. Short of about a foot they don't really focus at all, and rely on their whiskers. Like most predators they key in on movement. Taken together I think these features explain the behavior you've seen.