We’re smart people. We assume that there is a huge maze of difficulty to be negotiated when we’re trying to get from the superficial appearances to an understanding of how something works; we also assume that, given time and help we can navigate most of these mazes.
What we don’t tend to see is that the maze is still there when you’re trying to travel in the opposite direction, from a deep understanding of how things work back to an understanding of how things look. This fact explains the interface design of Linux, of course. But it has wider applications.