Something Apple is oft derided for is its treatment of factory workers. Both Tim Cook and Steve Jobs rightly bristled at such accusations. One of my first jobs at Apple was developing factory line software for the first iPhone...
The purpose of our station was primarily to charge the battery to make sure iPhones were fully charged when the user first took them out of the box. After all, nobody wants a dead iPhone.
But why just sit there waiting for a freshly-assembled iPhone to charge? Why not do something useful while waiting? And so, we developed a battery of tests that made sure iPhones functioned properly under stress. A smoke test, if you will.
However, consider the fact that several devices per second are moving down a manufacturing line, the being pulled off to charge. As you pull every device off the line, you very quickly have hundreds, thousands, tens-of-thousands of devices sitting around.
This is indeed how it was, and continues to be. However...consider that one of the tests we ran was to activate all RF-capable equipment on the device to make sure it actually works. Cell, BT, Wi-Fi, GPS, all on at the same time.
Picture: thousands of devices sitting in a factory room, running RF tests.
Do you have any idea how a microwave oven functions?
Indeed. We had to make sure that the room which contained iPhones running such tests was sufficiently RF transparent as to not cook anyone who might have entered; myself included.
So, rather than make the world's largest microwave oven, we took care. Such consideration might not seem obvious, or reasonable, but it's critical. Otherwise, I might not be sitting here relaying this story to you now.
Multiply the number of racks shown here by 50...