There are the sort of players who get distracted by the least little event occurring outside the game, and then run off on tangents discussing anything but what's happening in the game. Like about 90% of them.

And then there are the players who get everyone focused again by staying in character and stressing the urgency of the time being wasted by everyone else's characters just standing around and apparently not doing anything.

There is a kind of paradigm here that the GM can in fact consider in-game time to be passing while the players are busily discussing the latest TV shows or movies or whatever. Learn if your GM is one of these people. This knowledge will come in very handy in combat situations.

Transcript

Han: Hey, everyone. We got the ice cream!
GM: Ah, just in time. Here, take this note.
Chewbacca: What did we miss?
GM: Luke is the only pilot left. Vader is hot on his tail.
R2-D2: We're staring into the face of Death. It's awesome.
GM: Luke's deciding whether to try to destroy or capture the Peace Moon.
Han: Hmmm, tough. Or... you could destroy it and then capture it!
Leia: The Peace Moon is clearing Yavin! It's going to fire any second!
Luke: I'm... gonna take the shot.
R2-D2: Use the Force, Luke! Use the Force!!
[SFX]: < bzzt spip doip-ding bzzt spip >
Luke: No, I'm not using the damn Force! I'm taking the frakking shot!