What

[Vickie]

Waffling on instead of just shooting.

 

[Gallius17]

Being black in the eighties, instant death.

 

[Mikara]

Hehe that's a good one

How about -

Robert Thorn saying to the Nun in Omen "Yeah ok I'll take the kid. The wife will never notice"

 

[♥ Kaytee ♥]

Shop assistant in Pretty Woman
Big mistake. Huge.

 

[grandmajjandcali]

Having a bonk in Friday the 13th.

 

[jcaas07]

Surely Vincent's biggest mistake was going to the crapper and leaving his massive gun in the kitchen in Butch's Apartment

Or the young guys messing with Marcelus Wallace. "Marcellus Wallace don't like to be f****d by anybody except Mrs Wallace."

 

[viclioce]

Vincent Vega not having the safety on. Remember never point your gun unless you intend to shoot

 

[Smiley Riley:)]

Darth Maul failing to read number six on the Evil Overlord list! There would have been no Star Wars then!