Another one that occurred to me:
When a trained professional does something completely illogical in a dangerous situation.
For example, the movie Face/Off. At the beginning, an undercover FBI agent is on the plane with Caster and Pollux, posing as a stewardess. When shit hits the fan and Castor sees that Archer and his team have flooded the runway to try and catch them, he runs to the front of the plane next to the pilot to see them. At this point, the undercover agent whips out her gun, points it at Castor, and yells, "FBI!" Meanwhile, Pollux, who is completely in her blind spot, naturally then clocks her from behind with the briefcase, subdues her, and then moments later, Castor kills her. I am always like, uh, I am pretty sure a trained undercover agent who was considered good enough to be put on a plane with a dangerous, highly-known criminal like Castor would know better than to pull a gun on him, while leaving herself open to a blindside by the other dangerous criminal on board.