Form v function...
For a designer..... the Function would be a metaphor. The Form (if gears would work) is unimportant.
For an engineer that's reversed - an engineer would be concerned if the gears would work (Function).. doesn't matter how the look (form).
Designers are concerned with how things look, how easy things read, how dynamic things appear. It honestly does not matter if gears would be actually functional, they just need to look nice and maintain overall design continuity.