I've seen the picture of the iPhone Duo, still in the store, perched on a stand, its screen flickering with broken white lines.
Apple has touted testing the screen hinge, opening it mechanically thousands of times. The phone survived every test it was put through. Yet here it is, on the stand, with a broken screen.
Wait till the product meets its first customer.
I'm sure the tests worked in theory and in the delicate hands of its engineers. But customers' hands are anything but delicate. Remember Elon Musk's wrecking ball? They must have tested the Cybertruck's window beforehand, but it took just one person outside the test group to break the glass with a single throw.
I remember when my nephew was barely a year old, not even able to walk. I handed him a wooden spoon in the living room as a distraction while I ran to the kitchen to get some food. As soon as I got there, I heard a snap. I came back to find this little boy holding the spoon, broken in two. It was a hard spoon, and there was no way his one-year-old hands could break it in half, yet there was the proof in front of me.
So yes, Apple tested the rigidity of the screen with fancy machines, but the iPhone Duo never stood a chance against the customer's hands. Unless we are holding it wrong?