I recently purchased this watch, a Nixon Banks Leather. My purchase choice was entirely for style: I wanted something square, with a leather band, chronograph functions, and emphasis on design.
It relies on the Gestalt principle of prägnanz. This principle assumes that the mind perceives elements that do not exist in order to complete a full experience. Humans tend to organize sensory input in an orderly, regular, simple and symmetric manner. Even though the numbers of the dial are completely absent, we still believe they are there because a partial pattern exists.
The watch presents certain challenges to the user (the cost of function following form). A user must rely on previous knowledge of the universal time system, and knowing exactly where the numbers will exist.
I have confidence that I can determine a 90º angle with some accuracy. I know that top is 12 o’clock, right is 3 o’clock, down is 6 o’clock, and left is 9 o’clock. I also know that the shorter hand indicates hours, and longer hand indicates minutes.
Interestingly, if I want to set the watch to be accurate to the minute, I have to wait until 3:15 (AM or PM) so that I can align the long hand to the word “Nixon”.