Keeping watch is a time-honoured tradition in many games.

Because you know that the one time you don't post a watch will be the time that a pack of dire wolves attack during the night.

Transcript

GM: 3PO, R2, you see a squadron of Imperial guards entering the complex.
R2-D2: Why did they tell us to wait outside again?
[SFX]: < bedoip pating doosquee bibuzz ping >
C-3PO: To keep watch.
R2-D2: Job done, then.
[SFX]: < tazz >
C-3PO: We need to warn them.
R2-D2: If only Han had left us a radio.
[SFX]: < whir blip-doip fobuzz pating-pip-dok-kipgi-prow >
C-3PO: He did. He left us his radio.
Wicket: I better go tell the elders! {runs off}
GM: Han's radio crackles into life.
Major Derlin, 2nd Lord Clabburn of Hoth: {over radio} Major Derlin here. Multiple squadrons of troopers are attacking Shuttle's Landing. We're gloriously outnumbered! And holding firm.
R2-D2: This is so unfair!
[SFX]: < bloop >
C-3PO: Mmm. Nowhere to retreat to.
R2-D2: Two fights and I'm not in either of them!
[SFX]: < ep boppity doop boop >