Clockwise
I'm a utility guy. Wait, who says that? Not normal people. I know; I'm not normal—well maybe normal enough to know that nobody cares more about your Apple Watch face than you do. But that's OK. You have to look at it the most. You should care.
It's been amusing to me just how much attention all-else-equal smart people have spent resolving which, if any, of the clock faces offered in watchOS pre-2 are the best.
The fact that this is even a discussion at all is an interesting moment in the history of timepieces. Now that smart watches are a thing, "digital" and "analog" are user interface choices, not immutable consequences of hardware design.
It's not that I have anything against a modular or digital rendering of time. I just find analog clock faces—even animations of them—more pleasing to look at. In some ways, they're more practical too. When it comes to simply being aware of time, digital clocks offer unecessary precision.
I think that most natural human tasks can be comfortably dimensioned in 30–60-minute segments. Simply seeing how far the minute hand is from the top or bottom of the hour is usually enough for me—without even consciously processing the exact number of minutes. I think this is just more natural for the human mind, whose current form evolved long before the dawn of timepieces.
Our natural sense of time is tied to progression along predictable left-to-right paths: words across a page, days across a week, clock hands across the periphery of a clock face. In fact, clockwise motion describes the most predictable pattern observable to early humans, who where themselves hands on a clock. As Donn Lathrop explains:
Clockwise and counter-clockwise as we now know them seem to have derived from an accident of---as the real estate dealer said---location, location, location. In the Northern Hemisphere (in what is now Iraq), where the cradle of our civilization was rocked and the first written records were kept some 4,000 years ago, the early thinkers and teachers noted that their own shadows moved from left to right, as does the shadow of a stick or a sundial gnomon move from left to right during the course of the sun across the heavens.
So while analog clock faces on a smart watch are skeuomorphs of mechanical analog watches, so too were mechanical analog watches skeuomorphs of sundials.
The analog clock face captures the physical manifestation of time in a way that a digital clock can not.
I think a circular clock face also says something about the senseless symmetry of time within the scope of our lives: a well-worn path. An infinite loop. Every day, we make the same circular trip together—at the same rate.
The clock faces we carry aren't just little models of sundials; they tell our entire history in the universe. For all our worldly accomplishments, we're still strapped to the tiny blue tip of a year hand, swinging around a giant nuclear time bomb.