Basic Trope: A Genre Savvy person lampshades the impracticality of a plan that is more "in-universe" appropriate and suggests a much more simple, practical solution. The suggestion is usually denied or given an equally outrageous explanation.
The villain has an elaborate Death Trap that would probably take a few hours, if not days, to kill The Hero. A Mook points out that he has a loaded gun in his hand and could easily kill him then and there. The villain throws the Mook out a window.
The villain, upon hearing his minion's suggestion, says that the minion is right, pulls out a gun, and points it at the hero. He then marches the hero into a deathtrap, and says that it still wouldn't be as fun. However, at the end of the deathtrap, the villain is waiting with a gun...
The villan realizes the Mook is right. He finds a gun and while practicing for the big moment, realizes he's a lousy shot. And goes with the plan anyway.
Lampshaded: This trope by definition is a lampshading of Bond Villain Stupidity. "You never just shoot the heroes when you have the chance. You know they always escape!"
Invoked: The villain is looking for a new Number Two who exhibits some common sense, guts and initiative, and decides that someone who asks this question has potential for the job. Thus, he intentionally sets up a situation like this to see if any of his minions react appropriately.
"...And in case any of you smartasses want to question my plans and suggest I 'just shoot him', I'd just like to remind you beforehand that there's space in my Death Trap for two".
The minion doesn't bother asking the Big Bad, and shots the hero himself.
Discussed: "So, um... Does anybody want to point out to him that this 'overdramatic Death Trap' shtick never ever works?"
Conversed: Two characters watch a cartoon where the villain puts the hero into a deathtrap, and one asks the other why the bad guy never just shoots them in that sort of situation. Extra fourth wall points if the one doing the asking is the in-universe villain, who does the exact same thing when he gets the opportunity.
Deconstructed: Due to high turnover rate of minions (i.e. they get killed) who gainsay the villain on his Genre Blindness, the minions eventually lose all desire to take initiative or be helpful and stay far, far away from the villain when not explicitly ordered to. The villain ends up losing a lot of battles because his minions are too afraid to attempt to correct his Genre Blindness and is eventually killed during a one-on-one gloating session with a (seemingly) captured hero because nobody else was around.
Reconstructed: The masterless minions go on to work for a villain with better employee relations, whom they feel safer questioning. If pressed, the villain limits himself to explaining that he has worked very hard to reach the point at which he can kill the hero, and he's not going to have it over in a mundane and unsatisfying brief way when a longer, more ego-boosting, and more sadistic fashion can be dreamt up.