I wrote code used to design hardware semi-automatically. The size and complexity of the tinest chip make it impossible to check the finished hardware perfectly.

I wrote code used to design hardware semi-automatically. The size and complexity of the tinest chip make it impossible to check the finished hardware perfectly. But even if you somehow managed to check it once, nothing proves it's going to be unchanged for years and years you order it. Now add on top of that you have so many of them in one devices, and there are so many devices, and suddenly you can see how many wooden horses cross the border avec seconds.