Why do people think Eminem will make a song with justin Bieber?

Many Bieber fans I talked to are like sure Eminem will do a song with him, I'm convinced he won't, they say he will because when he wants something, it's gonna happen, I don't understand this arrogance. Bieber did even once performed an edited version of loose yourself, in which he failed and didn't even say the lyrics right, is this the same kind of arrogance?