While all dogs have some traits in common, for the most part, dogs have individual personalities just like humans. When you live with your puppy for a long time, you get to know these traits pretty well. And sometimes that can come in handy.
For instance, like when themegnugget asked:
Dog owners had the answers quickly.
Throw a ball.
He would be the one left standing there after all the other dogs had taken off after it.
Call his name and look for the one who thinks it's hilarious to run in the opposite direction.
My dog flips his sh-t when I make "binoculars" with my hands and look at him with them. Howls and barks and tries to attack me. He absolutely hates binoculars. I have a video of it somewhere. Two seconds...
Edit: here's the vid. I just remembered I answered a similar question about a year and a half ago and posted this vid as a response. Hope you like it.