Sometimes the quilt top gets out of "square" after piecing it all together. If your blocks weren't quite square when you assembled them into rows, or your seams are off a bit when adding sashing and borders, your quilt top may end up with sides that are unequal in size. Some times your top may be "squared up" and after you quilt, it is not anymore, due to the quilting. If this happens you measure and cut the top so that it is a true square or rectangle shape (Or in some cases round :wink:) before you add on the binding.