If you see an advertisement for a watch, chances are you'll see the watch's time set to 10:10.
Watchmakers have traditionally chosen 10:10 as their display time because it ensures that the watchmaker's logo, which is usually engraved beneath the 12, isn't obscured by the watch hands. On top of that, having the hands at 10:10 is symmetrical.
Apple, however, chooses to display a slightly different time on all of its Apple Watch promotions, setting the time one minute ahead to 10:09 rather than 10:10.
It's no mistake, either. Apple has a history of choosing a display time that has some significance, famously setting the time on all of its iPhone promotional materials and images to 9:41, the approximate time of day when Steve Jobs first unveiled the iPhone to the world back in 2007.
So why 10:09 for the Apple Watch? Apple appears to be making a statement about being ahead of the curve when it comes to smartwatches, and the facts back this theory up.
Many of the most famous watchmakers have a preference for the exact time displayed on their watches, according to Quartz. Rolex loves 10:10:31, TAG Heuer prefers 10:10:37, and Bell & Ross always opts for uniformity with 10:10:10. Timex, one of the few watchmakers who deviate from the 10:10 norm, displays the time 10:09:36.
Diving deeper, it appears that Apple wants the Apple Watch's time to be ahead of even Timex, and displays a specific time of 10:09:00 or 10:09:30, both of which allow Apple to consider itself "ahead of the times" with the Apple Watch.
So there you have it, it all boils down to Apple using a cheeky pun to symbolically stake its claim to the smartwatch market, all while tipping its hat to an age-old watchmakers tradition.
Update: Apple blogger Dave Mark over at The Loop has a different theory.
I think this is more about symmetry, about attention to detail, than about being ahead of the curve. At 10:10, the hour hand will be 1/6 of the way between the 10 and the 11 on the watch face. If the minute hand is precisely on the 2 (as it would be at 10:10), the minute and hour hands would not be symmetrical. At 10:09, the hands would be much closer to symmetrical perfection.
That sounds more like Apple logic to me.
Mark makes a great point, and his theory could also explain why the second hand is always at the 12 or the 6 position, as both maintain the symmetry of the watch face. Either way, there's no doubt that Apple was deliberate with its choice.