The main thing in our design is that we have to make things intuitively obvious,” Jobs told [a] crowd of design mavens. For example, he extolled the desktop metaphor he was creating for the Macintosh. “People know how to deal with a desktop intuitively. If you walk into an office, there are papers on the desk. The one on top is the most important. People know how to switch priority. Part of the reason we model our computers on metaphors like the desktop is that we can leverage this experience that we already have.
Steve Jobs by Walter Isaacson