Irrelevant Importance

Sometimes a game scenario requires the player to protect something or someone from destruction, so that it can be used by the player within the scenario itself. In some of these cases, should the object be destroyed after it has served this purpose this will still trigger a mission failure, because the game doesn't recognize that its further preservation is now irrelevant to the mission.

See also You Have Outlived Your Usefulness, the villainous, non-interactive version.


 * Hidden & Dangerous has at least two examples of this:
 * An early mission features an attack on an oil refinery in order to free some prisoners believed to be held there. They are not present, but a worker reveals under threat that they were taken to a certain location. At this point the player has learned all there is to know, and killing the informant shouldn't make any discernible difference (it can be justified as, say, covering one's traces). Yet if one does so, the mission will inexplicably fail.
 * Well, it would probably give the Germans a propaganda victory (in the cold-blooded murder of a noncombatant) and make relations with the Italian resistance difficult.
 * In another mission, the player had to destroy a water lock with the cannon of a parked tank. When this had been accomplished this one would think that one might as well blow up said tank, to deny its use to the enemy. Yet if this is done, the mission will fail, even if the lock is already destroyed.
 * In Rogue Spear there is a mission in which you must reach a computer and download some files from it. If one triggers the alarm too early a guard will press a button that sets off a charge that destroys the computer, resulting in mission failure. Said button can also be pressed by the player. If one finishes downloading the files and decides to use this button to destroy the now unimportant computer (to, again, deny the enemy further use of it), the mission will fail, even though the primary objective was accomplished and protecting the computer is no longer relevant.
 * In one of the missions found in the Collector's Edition of TIE Fighter, the objectives include shooting down a Pirate cruiser and all the fighters it carries. The cruiser itself is prevented from escaping by means of an Imperial interdictor cruiser. Occasionally, one will find one of the fighters will enter the pirate cruiser's hangar bay and thus be removed from the game map. The game interprets this as the fighter getting away, and the mission will immediately fail, even though the fighter would logically be destroyed whenever the pirate cruiser is.
 * In one mission, your objective involves the take over or destruction of a star cruiser, protecting various craft, and additionally eliminating an enemy squadron of fighters for some reason. It's very possible for AI Assault Gunboats to disable an enemy fighter's weapons and shields (with Ion Cannons) but not finish the job and disable the engines. The end result is that by the time you realize there is a single star-fighter left, which is completely unable to do anything or be of any threat, the ship is hundreds of kilometers away, resulting in you having to make a ridiculously long chase for over a half hour just to catch up with it and destroy it. This is beyond annoying.
 * In X-Wing Alliance, there is a mission to recapture the space station that belonged to the Azzameens from the mercenaries occupying it. When its defences fail, a transport will launch and quickly jump into hyperspace. Afterwards, NPCs will state that it looked like your uncle's ship. The targeting system marks it as hostile, its survival is irrelevant to the main objective and the last family mission involves the uncle betraying your family. Yet if he is shot down, the mission will fail, with comments that indicate the station was somehow lost.
 * Another mission requires the player to destroy a ship belonging to his family, and marked as such by the color-coded IFF system. Despite the fact that the mission cannot succeed unless this ship is destroyed, the player's helpful robot buddy will repeatedly insist that the player stop shooting.
 * GoldenEye never really let this happen, which was strange. Consider: in the Statue Park level, you can feel free to gun down Valentin after he's arranged your meeting with Janus, but he'll still be there, two levels later, if you're playing in the right difficulty level.
 * That's not the only example, either. In fact, it is possible with proper timing to gun down Big Bad virtually every time he appears, only for him to be there to taunt you next level.
 * The Control level is an exception to the above rule. Your main objective is to defend Natalya as she hacks the Goldeneye satellite in what is probably the most infamously difficult scene in the game. After a long and difficult fight, you still can't relax even after you've receive the message stating the satellite has been reprogrammed: In the few seconds between finishing her work and escaping to safety, Natalya can still be targeted by enemy guards, and her death will result in mission failure, despite the fact that—though it's pretty cold logic—she's outlived her usefulness. Then again, what's James Bond without his woman?
 * He's James Bond looking for his next woman.
 * That, and keep in mind that Janus is Dangerously Genre Savvy. You didn't permanently kill the Goldeneye off. You just put it into a gradual decaying orbit that will eventually destroy it. True to form, Janus has alternative ways to correct the sabotage you did to the Goldeneye, and while you don't need Natalya for those, you don't know that. And she also doubtless helps deal with security in the control to prevent anybody *else* like Boris from saving the satellite.
 * This is partially subverted in the same level: Shooting Boris to death after he completes his objective won't end the mission. However, Natalya will complain about watching you kill him over the security camera, and will then go back to the elevator, rather than disable the satellite, making the mission Unwinnable.
 * In the spiritual sequel, Perfect Dark, there was a major inversion: one level required you to carry a crate of bullet-sensitive explosives for a while to blow a hole in a wall. If they blew up while still relevant, you got the "Mission Failed" message, but it turns out they were never really relevant to begin with; there were other ways to blow the hole in the wall, and doing so would give you a "Mission Incomplete" message as the game realized you still had a chance.
 * Max Payne has an unusual version that would take some effort (or some very bad luck) to activate. Max grabs a junkie and forces him to tell his criminal friends to open the freaking Locked Wooden Door. If he dies before that, the fission is mailed. The moment the door opens, the junkie grabs a convenient gun and starts shooting at Max, leading to his untimely demise. But if he gets shot (by Max or his friends) after the door is opened but before he grabs the gun... you've guessed it.
 * It's actually even smaller a margin than that: the goon says the password to open the door, and the door unlocks. You can't shoot the guy then, as it's game over. As soon as the door opens, he screams "It's a trap!" and runs into the room: gun him down. Better yet, stand right behind him and the goons in the room will gun him down for you. He never actually gets to a gun.
 * The Elder Scrolls II: Daggerfall has an exploit during its "Cast the Sleep Spell" quest for the Mages Guild. You only have to prep the spell in the presence of the client NPC and can cancel it immediately afterwards, conserving your magicka and still accomplish the quest objective. Furthermore, after accomplishing the quest objective, you can kill the former client NPC without penalty.
 * Inversion: Perfect Dark and Goldeneye. Free the hostages, then wait a few seconds until the computer acknowledges this. Then feel free to hunt the hostages down and shoot them in the face. You won't fail the mission.
 * A few items in Illusion of Gaia can't be thrown away even after they become useless. This is irritating due to your limited inventory space, especially if you've been hoarding the Herbs you get throughout the game.
 * the same for every key item in Mother, also known as Earthbound Zero, alleviated by the fact you can leave stuff at home, freeing up the 8 slots per party member. But you'd need to go all the way there, until you get teleport.
 * In Cave Story, your inventory will be full of keys to doors you have already opened by the time you reach the game-end.
 * Fallout 3 and Fallout: New Vegas have this problem, and it can be a real pain when some of the items actually have weight. In New Vegas, for example, you can receive a machete at one point that cannot be sold, dropped, or disposed of, even in situations where all of your other weapons would be confiscated.