Git Gud - What does git gud mean?

Git Gud is slang for "Get good." See an example of how people use it.
Gamers use git gud (get good) to tell other players they need to up their game. Typically, gamers use this spelling when mocking another player's poor play. For example, if one player whines about how they're never lucky, the player's opponent may respond with nah, you just need to git gud.

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