This should include details about the Home Button Ribbon Cable. Unlike an iPad 3 (which doesn't have this cable) the iPad 4 has a Home Button Ribbon Cable that runs along the left side of the Home Button and is adhered to the glass. If the guitar pick is inserted too far (more than 0.5") it is possible to damage or sever this cable.

The second photo does not show the iPad 4's Home Button Ribbon Cable.