In relation to their body size, cats' eyes are enormous. Their pupils open much, much wider than ours do, so much so that they let in about five times more light. This, of course, makes them excellent nighttime hunters. Like most predators, they don't have much in the way of peripheral vision. Their total visual field covers about 200 degrees, with actual binocular vision in the 90–100 degree range—about the same as humans (that's right, you're a predator too).
Just as children who spend less time outdoors are more likely to be nearsighted, indoor cats tend to be nearsighted too. But regardless of whether they're raised indoors or out, there's a limit to a cat's near vision. Those huge eyes and pupils keep them from being able to focus clearly on anything closer than about 10 inches (25 centimeters) away, and by 4 inches (10 centimeters), all the squinting in the world won't let them see the object. Once an object is that close, other senses take over: their whiskers swing forward to feel what's in front of them, and their amazing sense of smell kicks in to identify the object. Still, that lack of super-close vision is why you can rustle a toy across the room and watch them immediately hone in on their feathery victim, but put a treat on the floor in front of them and they might as well be blind.
Related: Cat People vs. Dog People