To me, a three-watch collection is about versatility. If I?m spending five thousand bucks on timepieces, I need to have all my bases covered: they?ve each got to be watches that look and feel good with a tux and with a tee, in the woods or at the bar. Of course, I?m not going to buy three watches that do exactly the same thing, either. I wear a watch as an adventuring tool, and to look and feel good every day, and to dress up nice when I have to. Covering these bases also helps me pick three watches that are distinct enough from each other to not want to head over to /r/watchexchange every few months. 
The other fun test I like to run in my head for a watch I?m thinking of buying goes something like this: Fifty years from now, if my kid or grandkid were to find one of these watches in my desk drawer, would they make me look cool" I think each of these three will make them think Grandpa was a real cool cat, regardless of the truth.
Seiko SNJ025 “Solar Arnie”

This is my ideal watch for roughing it. For fly fishing and camping, it?s great to have a watch you can roll out of a sleeping bag with and never think twice about breaking it. An analog-digital diver that?s a direct homage to the Seiko H558-5009 Arnold Schwarzenneger wore in Predator (Roger Moore wore one as Bond, too, btw) does just the trick. It?s got more water resistance than I?ll ever need, its solar quartz movement will keep on ticking indefinitely if it gets sun, the tiny digital scree...