'Get that shit out' is an expression, usually out of annoyance, similar to gtfo
. However, it can be used indirectly, towards objects for example. It is also used to show dominance over a thing.
Credit can go to a young man named Sam S. for inventing the term.
A basketball player goes up for a slam dunk, and another player knocks the ball out of his hand while yelling, "Get that shit out!" Thus it is refering both to the basketball and to the player's attempt at scoring.
A waiter brings you something that you didn't order, you can simply say, "Get that shit out," in a Mr. T voice.
You can say "Get that shit out," as you throw an object off a cliff in rage.