Go Team!

I've often pondered the "Go..." phrase that's used in sports.

“Go, Tigers!”

“Go, Rockets!”

“Go, Astros!”

Frankly, the metaphor's meaning escapes me.

Go??

Go where?

Go how far?

Do you want them to come back?

Or just Go and stay?

While they're going, do they need to stop and pick something up on the way for you?

"Go Flyers..." unless you can't fly. Or the TSA stops you.

Would you still yell, "Go Flyers," knowing that it might involve an invasive x-ray scan of your body?

Would you still tell the Flyers to "Go" if you thought they'd be held up at the security check point? Should you instead say, "Go, Flyers, once you've passed security"?

If the Flyers are doing really well, why would you even want them to leave?

If they "Go," when would it be appropriate to return? 

Perhaps the time to tell a team to "Go" is when they're losing. 

Or their season really sucks.
Like "Go Texans."

Git.