#### Ryumast3r

It doesn't equal 4 because, no matter how many times you cut the squares smaller and smaller, there will always be area of the squares that is not touching the circle.

Here's a little picture I drew in paint to help visualize:

In the above picture, there is a section of it that is red. You'll notice that this area exists on the other pictures as well (but it's blue, I believe). This area, no matter how many times you cut away at the square, still exists to an extent. At some point, it's a very small extent, but the upper-right corner of the square will never touch the circle, there will always exist 2 more upper-right corners for every single upper-right corner that you cut away.