One of my favorite things about the Apple Watch is that it keeps uncannily good time. Put two next to each other and you'll see what I mean.

I always found it disappointing that even the best mechanical watches drift by around a second a day. I guess growing up with software has given me unrealistic mechanical expectations :)

No no - my 70 year old Russian mechanical watch is "that inaccurate"... (My Pebble's, and presumably the Apple Watch, sync themselves from what I assume is one of or some combination of ntp time, GSM/LTE time, or GPS time - from the phone they're paired with...)