"Take the thumbscoop, for example. It’s the indentation that allows you to open the display. If the scoop is too deep, you put too much pressure on the display to open it. If it’s too shallow, you struggle to open the display. It may seem incidental, but if the thumbscoop is well designed, it makes the difference between a bad experience and a good one. The challenge of the thumbscoop was to create a crisply machined scoop that was still comfortable to use. The designers at Apple worked on hundreds of versions of the thumbscoop — even examining them under an electron microscope — to get it right."