A player fixating on one tiny aspect of the greater picture can cause dischord. It's important to keep your players from going off on a tangent when there's a clear story arc you want them to encompass.

Transcript

Luke: I can't shake him!
Wedge: I got your tail, good buddy.
[SFX]: Pow! Pow!
Luke: Great, now I'm much less worried.
Wedge: Hold still just a second, I have to aim really straight here.
Luke: Allow me to gesticulate wildly exactly how much I will be dodging at this point.
[SFX]: Pow! Pow!
Wedge: You're making it real hard for me here, buddy... Here goes.
Luke: Wiggle the shanty lever! I think!
GM: Wedge fires and... <roll>... hits...
GM: The PIE fighter.
[SFX]: Kaboom!
Luke: Woo! Two PIEs are squared away!
R2-D2: The circle is now complete.