History MotiveDecay / LiveActionTV

* ''Series/{{V}}'': In the original series, which followed the mini-series and ''The Final Battle'', the visitors seem to have abandoned their original plan to steal all of Earth's water and use the people for food and have instead chosen to enslave the people for some reason. Even though they still use people for food, this appears to be a secondary motive rather than the primary purpose as it was in the original miniseries.

* ''Series/{{Community}}'': The original reason the study group was formed was so [[TallDarkAndSnarky Jeff]] could seduce [[GranolaGirl Britta]]. This premise stopped being mentioned about half way through the first season, and towards the end of the third even the study group was temporarily dropped as an excuse to keep the group together. This does not go without a [[LampshadeHanging Lampshade]].

* ''Series/{{Heroes}}'': Sylar's motivation has gone from "I want to be special" (first series) to "I have an uncontrollable Hunger which makes me lust after killing to get people's abilities" (second). By the third, though, he seemed to have decided that "this is just who I am and I'm happy with it." Now his aim seems to be simply KillAllHumansWithAbilities - Danko points out that "if we succeed, you'll be the only one left", and Sylar just smiles and agrees. After, he want to be the President replacing the actual. In final season, he want to be a good person. Believing that, without his abilities, he would not be a monster, Sylar asks Matt to rid him of them.

* ''Series/{{Heroes}}'': Sylar's motivation has gone from "I want to be special" (first series) to "I have an uncontrollable Hunger which makes me lust after killing to get people's abilities" (second). By the third, though, he seemed to have decided that "this is just who I am and I'm happy with it." Now his aim seems to be simply KillAllHumans With Abilities - Danko points out that "if we succeed, you'll be the only one left", and Sylar just smiles and agrees. He doesn't even need to kill to steal abilities any more either.

* ''Series/BattlestarGalacticaClassic'': The episode ''Space Croppers'' begins with the Galactica's fleet being attacked by the Cylons. The Cylons destroy the fleet's food supplies. Boy genius Dr. Zee comes up with a plan to send Troy and Dillon down to Earth to get some supplies. Troy and Dillon pick a farm at random and soon find out that the farmer is having problems with the local growers' association. Instead of picking another farmer to get supplies from, the motive decays into helping this farmer out with his problems and the rest of the episode revolves more around helping a farmer than it does about getting food for Galactica.

* ''{{Glee}}'':

* ''TheOffice'': In one episode, after Michael Scott left the show and Andy Bernard is in charge, Andy is having a family crisis trying to provide for his mother after his father skips town. For some reason that isn't explained in the show, everyone in the office is working on helping Andy with his problem, all on company time and none of them seem to think there's anything wrong with that. Instead of selling paper, they all work on Andy's problem as if it's what they're supposed to be doing.

** Lord Zedd and Rita Repulsa suffer from this. They go from wanting to conquer the Earth to wanting to destroy the Power Rangers, or even simply just ruining their day. Sure, if they get rid of the Rangers, they'll be free to rule the planet, but their plans noticeably go from "This plan will provide us with an unending power source or ultimate weapon that will allow us to take over the Earth" to "This plan will ruin Kimberly's chance at joining the Pan Global Games."

** It was always more of "principle of the matter" kind of thing. Before the Glee club, the Cheerios were the only shining light in a highschool of mediocrity; the football hasn't won a game in years, most everyone grows to get a job and live in the same town, and by being the best of the worst, the cheerleading squad dominated. And Sue liked being on top, with all the control. Even in the first episode, Sue could see that the Glee club had potential, potential that would take the light away from her team (and her), so she did all she could to make it not happen.

* ''Series/BreakingBad'':
** A major plot point. By season three Walter's entire motive to be a drug dealer is gone. His family has abandoned him, the money is no use for them, let alone for him to spend, but he ''likes it'' and is trying to rationalize what he is and what he has done. Particularly notable is that when he finally gets to cook meth as a quiet day job with no thrills he requests Jesse back and spends an episode trying to kill a fly. Jesse, on the other hand knows he's just a bad man.
** He tells himself that he's still doing it to provide money and protection to his family (who are clearly at risk, since he's gotten in so deep). But it's made clear that these are justifications to do what he wants to do anyway. As of season 5, Walt's only motivations are money and stroking his own ego. Since [[spoiler: Walt killed his boss, the main person threatening his family]], and he has enough money to cover his family, the only thing putting everyone in danger is Walt not quitting while he's ahead. In the finale, [[spoiler:he finally admits that his family was always just an excuse, and he did what he did because he liked it.]]

*** The series had been indicating that Faith didn't really fit into the group nearly since her introduction. Her handling of combat boils down to 'stay out of my way, and don't expect me to babysit you' - an attitude that almost gets Buffy killed, and clashes with the Buffy crew's normal 'no man left behind' tactics. It is also indicated that she has a simplistic view of social relationships: she respects strength, and she respects loyalty... and doesn't necessarily care about good or evil. She takes the scoobies' criticisms as indications that she isn't accepted by them, and ultimately loses respect for them when they all take issue with her might-makes-right life philosophy. She readily adopts the BigBad as her leader/father figure because he's strong and ruthless, yet loyal to Faith and appreciative of her efforts.

** Willow gets this after Tara's death. Killing Warren was bad enough, given ThouShaltNotKillMuggles. Going after [[IneffectualSympatheticVillain Johnathan and Andrew]] causes Buffy to try and stop her. When Giles intervenes she changes motives to [[MercyKill destroy the world.]]

* ''{{Bones}}''; recurring villain Christopher Pelant started out as a self-proclaimed "Hacktivist" whose grisly string of murders were supposed to have a political message. His most recent episodes have him concentrating on Booth and the Jeffersonian team (seeking revenge against Booth in particular, for severely scarring his face with a gunshot).

* ''MightyMorphinPowerRangers'':

* ''{{V}}'': In the original series, which followed the mini-series and ''The Final Battle'', the visitors seem to have abandoned their original plan to steal all of Earth's water and use the people for food and have instead chosen to enslave the people for some reason. Even though they still use people for food, this appears to be a secondary motive rather than the primary purpose as it was in the original miniseries.
* ''TheWildWildWest'': In his earliest appearances, Dr. Miguelito Loveless was depicted as a WellIntentionedExtremist, who just wanted to regain part of California, which was stolen from his ancestors (although he was willing to kill over a hundred people to do so) and share his inventions with the world. By the second season, he had become a garden variety MadScientist whose schemes revolved around either conquering the United States [[TakeOverTheWorld or the world, sometimes]] or getting revenge on James West.

** He tells himself that he's still doing it to provide money and protection to his family (who are clearly at risk, since he's gotten in so deep). But it's made clear that these are justifications to do what he wants to do anyway. As of the season 3 finale, this appears set to change, as he has observed the consequences of his actions.
*** Sadly things did not change, and as of season 5 Walt's only motivations are money and stroking his own ego. Since [[spoiler: Walt killed his boss, the main person threatening his family]], and he has enough money to cover his family, the only thing putting everyone in danger is Walt not quitting while he's ahead.

* ''{{Bones}}''; recurring villain Christopher Pelant started out as a self-proclaimed "Hacktivist" whose grisly string of murders were supposed to have a political message. His most recent episodes have him concentrating on Booth and the Jeffersonian team(seeking revenge against Booth in particular, for severely scarring his face with a gunshot).

* ''HighwayToHeaven'': In the episode ''For the Love of Larry'', a man and his boy are missing. Johnathan and Mark find the dog that was with them when they went missing. The Sheriff runs into Mark and Johnathan and shows them a picture of the missing man and boy with the dog. They explain that they found the dog, which is now in their rented cabin. Instead of asking them to take him to where they ''found'' the dog (as a good place to start looking for the missing man and boy), the sheriff asks them to take him to where the dog is ''now'' and when they find out the dog is missing, they start looking for the dog. The motive decay here is that they stop looking for a man and boy and start searching for the dog while two people are still missing. What was finding the dog going to do?

* ''{{Bones}}''; recurring villain Christopher Pelant started out as a self-proclaimed "Hacktivist" whose grisly string of murders were supposed to have a political message. His most recent episodes have him simply seeking revenge against Booth and the Jeffersonian team(Booth in particular, for severely scarring his face with a gunshot).

* ''{{Bones}}'';
** Recurring villain Christopher Pelant started out as a self-proclaimed "Hacktivist" whose grisly string of murders were supposed to have a political message. His most recent episodes have him simply seeking revenge against Booth and the Jeffersonian team(Booth in particular, for severely scarring his face with a gunshot).

** Willow gets this after Tara's death. Killing Warren was bad enough, given ThoughShallNotKillMuggles. Going after [[IneffectiveSympatheticVillain Johnathan and Andrew]] causes Buffy to try and stop her. When Giles intervenes she changes motives to [[MercyKill destroy the world.]]

* ''Series/BreakingBad'': A major plot point. By season three Walter's entire motive to be a drug dealer is gone. His family has abandoned him, the money is no use for them, let alone for him to spend, but he ''likes it'' and is trying to rationalize what he is and what he has done. Particularly notable is that when he finally gets to cook meth as a quiet day job with no thrills he requests Jesse back and spends an episode trying to kill a fly. Jesse, on the other hand knows he's just a bad man.

* ''Series/BuffyTheVampireSlayer'': Warren Mears was subjected to this in between seasons five and six. He built a subservient robot girlfriend because he was lonely, but found that he actually preferred a real-life girl who was his intellectual equal and "[[ILoveYouBecauseICantControlYou gave him a hard time]]". Xander even expressed sympathy for him (although he was undeniably a pervert). Yet by season six he's a full-out misogynist who Xander "could see as a SuperVillain type."

* ''Series/DoctorWho'': Mandatory example: When they first appeared, the Cybermen, who at the time appeared roughly half-human, not mostly machine, had plausible motive for their villainy: they had become fixated with survival at all costs. By their fourth appearance the rails had begun to come off this idea and from then on, [[DependingOnTheWriter they've have various different motivations ascribed to them]].

* ''Series/{{Farscape}}'': Has a positive example. Captain Crais's original motive for hunting down Crichton was to avenge the accidental death of his brother. This was something a simple discussion with Crichton could have cleared up, so the writers let them ''have'' that conversation, but in the context of a duel to the death that left Crais angry for a better reason: John won the fight and nearly killed him. Later, when Crais had more or less {{Heel Face Turn}}ed, he had ''another'' new motive for getting rid of Crichton: they were both in love with Aeryn.

* ''{{Glee}}'': Sue Sylvester initially hated the Glee club because it was taking funding away her cheerleading team, the Cheerios. It later becomes clear that the Cheerios have boosters who "write fat checks" which take care of most of their expenses, and it seems Sue's machinations to take down the Glee club come from either a personal vendetta against Will Schuester [[ForTheEvulz or just a perverse love for stirring up conflict.]]

* ''Series/KnightRider'': KARR. In "Trust Doesn't Rust", KARR's villainous acts are clearly the result of his childlike understanding of the world being misled by two petty thieves, combined with the LiteralGenie aspect of his prime directive of self-preservation. When he reappears in "KITT vs KARR", he is simply evil, lusts for revenge against KITT, and seems unconcerned about his own survival. Neither Michael nor KITT find this odd, and the characters even know ahead of time that KARR is insane and out for revenge.

* ''Series/LittleHouseOnThePrairie'': In the episode, "Family Quarrel", Nels and Harriette Oleson have separated and Nels is living in the hotel. Doc Baker and Mr. Hanson get the idea that Mr. Hanson should go ask Harriette out on a date. The reasoning is that Nels will get jealous and will want Harriette back. In the next scene, Hanson is wearing a suit and carrying some flowers as he and Doc Baker walk toward the mercantile store. Doc Baker tells Hanson that now is a good time because Nels is out of town and won't find out. This subverts the original purpose, which was to make Nels jealous.

* ''Series/LogansRun'': Logan and Jessica in the TV series start out on a trip to find sanctuary. They say they're looking for it so they can go back and tell other people about it so they don't have to die on Last Day at Carousel. However, as soon as they're outside the city, they go on all kinds of adventures, sometimes abandoning common sense to allow these adventures to happen, like in one episode, they meet a man who says he'll take them to his city, but they have to abandon their vehicle and weapons. They gladly agree and trouble follows. The whole time they're looking for sanctuary, they could just go back and tell the people in the domed city that there's life outside and that it will be rough, but it beats dying at 30. Instead, they keep looking for sanctuary.

* ''MightyMorphinPowerRangers'': Lord Zedd and Rita Repulsa suffer from this. They go from wanting to conquer the Earth to wanting to destroy the Power Rangers, or even simply just ruining their day. Sure, if they get rid of the Rangers, they'll be free to rule the planet, but their plans noticeably go from "This plan will provide us with an unending power source or ultimate weapon that will allow us to take over the Earth" to "This plan will ruin Kimberly's chance at joining the Pan Global Games."
** When Rita escaped her jar the second time, after being imprisoned in there due to Zedd taking over her [[SpaceBase Moon Base]], she went from getting revenge on Zedd for imprisoning her via an overly complicated scheme involving marrying him to... Just... Sort of nagging him constantly due to his inability to kill the Power Rangers while she's just as unsuccessful at it herself.

* ''Series/{{Revolution}}'': Charlie's search for Danny. She says she needs to get to him as soon as possible so as to avoid him being in danger too long, but sees it necessary to [[ChronicHeroSyndrome save literally every person]] they come across along the way who isn't with the militia, putting herself and her group in danger every time for people who they'll most likely never see again. This would be an InUniverse trope, but, over time, the rest of the cast doesn't even call her out on it. [[spoiler: Rendered moot as of episode 10, due to Team Matheson rescuing Danny. Episode 11 ends with Danny getting killed off]].
* ''Franchise/StarTrek'': The Borg had a small dose of this. Their goal started off as conquering and gaining knowledge. If possible, they would steal technology (most weapons don't work on them or they adapt) and just leave after maybe screwing the other side over a little bit more. Many times they would just destroy enemy ships. They would absorb a being of another species only when they needed information that you couldn't get from a computer (or they needed an ambassador). Come Voyager and the Borg seemed to have "adapted" and are now simply trying to absorb every species, conquering the universe, and stealing technology with absorbing species as the priority instead of as an afterthought.

* ''Series/BreakingBad'': A major plot point, and proof that TropesAreTools. By season three Walter's entire motive to be a drug dealer is gone. His family has abandoned him, the money is no use for them, let alone for him to spend, but he ''likes it'' and is trying to rationalize what he is and what he has done. Particularly notable is that when he finally gets to cook meth as a quiet day job with no thrills he requests Jesse back and spends an episode trying to kill a fly. Jesse, on the other hand knows he's just a bad man.

* ''Series/{{Community}}'': The original reason the study group was formed was so [[TallDarkAndSnarky Jeff]] could seduce [[GranolaGirl Britta]]. This premise stopped being mentioned about half way through the first season, and towards the end of the third even the study group was temporarily dropped as an excuse to keep the group together. This does not go without a [[LampshadeHanging Lampshade]].

* ''Series/TheTomorrowPeople'': Jedekiah. In "Break Out", the shapeshifting android was not really villainous, but was perpetrating his apparently-evil deeds because he was under orders from a kind alien who mistakenly believed humans to be dangerous and barbaric. In his various reappearances, Jedekiah is simply evil, and obsessed with revenge, conquest, and the eradication of homo superior -- and the Tomorrow People already seem to know this to be his natural personality ahead of time.
* ''Series/BreakingBad'': A major plot point, and proof that TropesAreTools. By season three Walter's entire motive to be a drug dealer is gone. His family has abandoned him, the money is no use for them, let alone for him to spend, but he ''likes it'' and is trying to rationalize what he is and what he has done. Particularly notable is that when he finally gets to cook meth as a quiet day job with no thrills he requests Jesse back and spends an episode trying to kill a fly. Jesse, on the other hand knows he's just a bad man.
** He tells himself that he's still doing it to provide money and protection to his family (who are clearly at risk, since he's gotten in so deep). But it's made clear that these are justifications to do what he wants to do anyway. As of the season 3 finale, this appears set to change, as he has observed the consequences of his actions.
*** Sadly things did not change, and as of season 5 Walt's only motivations are money and stroking his own ego. Since [[spoiler: Walt killed his boss, the main person threatening his family]], and he has enough money to cover his family, the only thing putting everyone in danger is Walt not quitting while he's ahead.
* ''Series/TwentyFour'': Vladimir Bierko. Bierko's original plan was to assassinate the Russian president in the name of their separatist cause and attempt to blackmail President Logan into not opposing them. Once Logan didn't fulfill his end of the bargain, he switched into all out revenge on the U.S. and CTU, culminating in taking over a nuclear submarine with the purpose of destroying several cities, his original goal forgotten. The stupidest aspect of this is that his [[TheDragon subordinate]], Ivan Irwich, went through the ''exact same pattern'' earlier in the season (being focused on his goal to assassinate the Russian President, getting betrayed by the US then seeking petty revenge on the US). Then Bierko makes his on screen debut... and immediately kills Irwich for deviating from their goals, the exact same thing he would do two episodes later.
* ''{{V}}'': In the original series, which followed the mini-series and ''The Final Battle'', the visitors seem to have abandoned their original plan to steal all of Earth's water and use the people for food and have instead chosen to enslave the people for some reason. Even though they still use people for food, this appears to be a secondary motive rather than the primary purpose as it was in the original miniseries.
* ''Series/CriminalMinds'': It's not so much that his motive got decayed, more like retconned, but the SerialKiller known as the Fox had something like this happen to him when he was brought back in the season five episode "Outfoxed". His crimes as revealed in his original appearance were breaking into the houses of families, then taking them all hostage and forcing them to treat him as the head of the household before eventually leading them down to the basement and killing them all, saving the father for last. In "Outfoxed" it was implied that he sexually abused the children he took hostage, and it was suggested that his crimes were essentially him lashing out at his abusive father and also at himself. In his first appearance, there had been no hint of a sexual component to his crimes and the reason given for his behaviour was that his wife and kids had left him and he was trying to recapture what it was like to have them, with him killing the families at the end because he knew the fantasy couldn't last.

* ''Series/{{Merlin}}'': Morgana started season three as a vengeful young woman who was out to avenge her own people against the genocide King Uther had committed against those who used magic. Since finding out that [[spoiler: Uther is her biological father]] she's moved from WellIntentionedExtremist territory into flat-out evil, most recently manipulating her best friend's feelings for Prince Arthur (her own [[spoiler: half brother]] who has never done anything to her) in order to try and assassinate her way to the throne of Camelot.
* ''Series/LittleHouseOnThePrairie'': In the episode, "Family Quarrel", Nels and Harriette Oleson have separated and Nels is living in the hotel. Doc Baker and Mr. Hanson get the idea that Mr. Hanson should go ask Harriette out on a date. The reasoning is that Nels will get jealous and will want Harriette back. In the next scene, Hanson is wearing a suit and carrying some flowers as he and Doc Baker walk toward the mercantile store. Doc Baker tells Hanson that now is a good time because Nels is out of town and won't find out. This subverts the original purpose, which was to make Nels jealous.
** In the episode "Haunted House", Nellie and Willy dare Laura to go up to a haunted house. She runs away scared. Later, to redeem herself, she approaches the house again, but is discovered by the owner of the home. She ends up forming a friendship with the owner and never tries to prove her bravery again, even though it was an important plot point and her motivation for approaching the house in the first place.
* ''Series/BattlestarGalacticaClassic'': The episode ''Space Croppers'' begins with the Galactica's fleet being attacked by the Cylons. The Cylons destroy the fleet's food supplies. Boy genius Dr. Zee comes up with a plan to send Troy and Dillon down to Earth to get some supplies. Troy and Dillon pick a farm at random and soon find out that the farmer is having problems with the local growers' association. Instead of picking another farmer to get supplies from, the motive decays into helping this farmer out with his problems and the rest of the episode revolves more around helping a farmer than it does about getting food for Galactica.
* ''HighwayToHeaven'': In the episode ''For the Love of Larry'', a man and his boy are missing. Johnathan and Mark find the dog that was with them when they went missing. The Sheriff runs into Mark and Johnathan and shows them a picture of the missing man and boy with the dog. They explain that they found the dog, which is now in their rented cabin. Instead of asking them to take him to where they ''found'' the dog (as a good place to start looking for the missing man and boy), the sheriff asks them to take him to where the dog is ''now'' and when they find out the dog is missing, they start looking for the dog. The motive decay here is that they stop looking for a man and boy and start searching for the dog while two people are still missing. What was finding the dog going to do?
* ''Series/TheXFiles'': The original motivation of Fox Mulder was to find his abducted sister. This actually weaves in and out of the story for a good four years, but then it's dropped nearly entirely. When he ''does'' find her, it turns out she was killed, not abducted, and is a ghost child running around a field. What should have been the ultimate climax of the story arc becomes a little sidenote a few years before the series actually ends.

* ''TheWildWildWest'': In his earliest appearances, Dr. Miguelito Loveless was depicted as a WellIntentionedExtremist, who just wanted to regain part of California, which was stolen from his ancestors (although he was willing to kill over a hundred people to do so) and share his inventions with the world. By the second season, he had become a garden variety MadScientist whose schemes revolved around either conquering the United States [[TakeOverTheWorld or the world, sometimes]] or getting revenge on James West.

* ''Series/{{Babylon 5}}'': The heroes defeat [[spoiler:the Vorlons and the Shadows]] by forcing them to acknowledge their Motive Decay. The most damning thing which ultimately convinces them to leave the galaxy is that they don't have [[spoiler:answers to their own Armor Piercing Questions anymore. The Vorlons no longer know who they are, and the Shadows don't know what they want.]]

* On ''Series/{{Community}}'' the original reason the study group was formed was so [[TallDarkAndSnarky Jeff]] could seduce [[GranolaGirl Britta]]. This premise stopped being mentioned about half way through the first season, and towards the end of the third even the study group was temporarily dropped as an excuse to keep the group together. This does not go without a [[LampshadeHanging Lampshade]].
* Irina Derevko on ''Series/{{Alias}}'' was an unfortunate victim of this trope. In season two, when she was [[spoiler: revealed as The Man, responsible for all the torture Sydney went through]], it was explained away as Irina playing a role for Khasinau, who thought he was the real leader. Her betrayal of Jack Bristow was also subsequently explained as her being an unwilling pawn of the KGB, forced to marry an American agent to find out about Project Christmas and then fake her own death. During Sydney's [[spoiler: missing two years]], she and Jack team up to hunt for their daughter. When it becomes known that [[spoiler: Irina has been doubled, and Jack shot the double, not the real Irina]], she becomes a valuable asset to the CIA, and rather than let them take her back into custody, Jack lets her go. She repays him by helping deliver Sydney's daughter, even though she really has been trying to kill them both as part of her "plan". After ''all'' these shades of gray, she's revealed in the series finale as your stereotypical CardCarryingVillain, [[spoiler: wanting to kill Sydney and everyone else in existence in order to bring about Rambaldi's "endgame". She is given a KarmicDeath, killed by Sydney as she tries to make her Great Escape before TheEndOfTheWorldAsWeKnowIt.]]
* Warren Mears was subjected to this in between seasons five and six of ''Series/BuffyTheVampireSlayer''. He built a subservient robot girlfriend because he was lonely, but found that he actually preferred a real-life girl who was his intellectual equal and "[[ILoveYouBecauseICantControlYou gave him a hard time]]". Xander even expressed sympathy for him (although he was undeniably a pervert). Yet by season six he's a full-out misogynist who Xander "could see as a SuperVillain type."

* Mandatory ''Series/DoctorWho'' example: When they first appeared, the Cybermen, who at the time appeared roughly half-human, not mostly machine, had plausible motive for their villainy: they had become fixated with survival at all costs. By their fourth appearance the rails had begun to come off this idea and from then on, [[DependingOnTheWriter they've have various different motivations ascribed to them]].

* ''Series/{{Farscape}}'' has a positive example. Captain Crais's original motive for hunting down Crichton was to avenge the accidental death of his brother. This was something a simple discussion with Crichton could have cleared up, so the writers let them ''have'' that conversation, but in the context of a duel to the death that left Crais angry for a better reason: John won the fight and nearly killed him. Later, when Crais had more or less {{Heel Face Turn}}ed, he had ''another'' new motive for getting rid of Crichton: they were both in love with Aeryn.

* Sue Sylvester of ''{{Glee}}'' initially hated the Glee club because it was taking funding away her cheerleading team, the Cheerios. It later becomes clear that the Cheerios have boosters who "write fat checks" which take care of most of their expenses, and it seems Sue's machinations to take down the Glee club come from either a personal vendetta against Will Schuester [[ForTheEvulz or just a perverse love for stirring up conflict.]]

* In ''Series/{{Heroes}}'', Sylar's motivation has gone from "I want to be special" (first series) to "I have an uncontrollable Hunger which makes me lust after killing to get people's abilities" (second). By the third, though, he seemed to have decided that "this is just who I am and I'm happy with it." Now his aim seems to be simply KillAllHumans With Abilities - Danko points out that "if we succeed, you'll be the only one left", and Sylar just smiles and agrees. He doesn't even need to kill to steal abilities any more either.
* KARR, from ''Series/KnightRider''. In "Trust Doesn't Rust", KARR's villainous acts are clearly the result of his childlike understanding of the world being misled by two petty thieves, combined with the LiteralGenie aspect of his prime directive of self-preservation. When he reappears in "KITT vs KARR", he is simply evil, lusts for revenge against KITT, and seems unconcerned about his own survival. Neither Michael nor KITT find this odd, and the characters even know ahead of time that KARR is insane and out for revenge.

* Jedekiah from ''Series/TheTomorrowPeople''. In "Break Out", the shapeshifting android was not really villainous, but was perpetrating his apparently-evil deeds because he was under orders from a kind alien who mistakenly believed humans to be dangerous and barbaric. In his various reappearances, Jedekiah is simply evil, and obsessed with revenge, conquest, and the eradication of homo superior -- and the Tomorrow People already seem to know this to be his natural personality ahead of time.
* A major plot point, and proof TropesAreTools, is ''Series/BreakingBad''. By season three Walter's entire motive to be a drug dealer is gone. His family has abandoned him, the money is no use for them, let alone for him to spend, but he ''likes it'' and is trying to rationalize what he is and what he has done. Particularly notable is that when he finally gets to cook meth as a quiet day job with no thrills he requests Jesse back and spends an episode trying to kill a fly. Jesse, on the other hand knows he's just a bad man.

* Vladimir Bierko in ''Series/TwentyFour''. Bierko's original plan was to assassinate the Russian president in the name of their separatist cause and attempt to blackmail President Logan into not opposing them. Once Logan didn't fulfill his end of the bargain, he switched into all out revenge on the U.S. and CTU, culminating in taking over a nuclear submarine with the purpose of destroying several cities, his original goal forgotten. The stupidest aspect of this is that his [[TheDragon subordinate]], Ivan Irwich, went through the ''exact same pattern'' earlier in the season (being focused on his goal to assassinate the Russian President, getting betrayed by the US then seeking petty revenge on the US). Then Bierko makes his on screen debut... and immediately kills Irwich for deviating from their goals, the exact same thing he would do two episodes later.
* In ''{{V}}'' the original series, which followed the mini-series and ''The Final Battle'', the visitors seem to have abandoned their original plan to steal all of Earth's water and use the people for food and have instead chosen to enslave the people for some reason. Even though they still use people for food, this appears to be a secondary motive rather than the primary purpose as it was in the original miniseries.
* It's not so much that his motive got decayed, more like retconned, but in ''Series/CriminalMinds'', the SerialKiller known as the Fox had something like this happen to him when he was brought back in the season five episode "Outfoxed". His crimes as revealed in his original appearance were breaking into the houses of families, then taking them all hostage and forcing them to treat him as the head of the household before eventually leading them down to the basement and killing them all, saving the father for last. In "Outfoxed" it was implied that he sexually abused the children he took hostage, and it was suggested that his crimes were essentially him lashing out at his abusive father and also at himself. In his first appearance, there had been no hint of a sexual component to his crimes and the reason given for his behaviour was that his wife and kids had left him and he was trying to recapture what it was like to have them, with him killing the families at the end because he knew the fantasy couldn't last.
* Logan and Jessica in the TV series of ''Series/LogansRun'' start out on a trip to find sanctuary. They say they're looking for it so they can go back and tell other people about it so they don't have to die on Last Day at Carousel. However, as soon as they're outside the city, they go on all kinds of adventures, sometimes abandoning common sense to allow these adventures to happen, like in one episode, they meet a man who says he'll take them to his city, but they have to abandon their vehicle and weapons. They gladly agree and trouble follows. The whole time they're looking for sanctuary, they could just go back and tell the people in the domed city that there's life outside and that it will be rough, but it beats dying at 30. Instead, they keep looking for sanctuary.

* Lord Zedd and Rita Repulsa from ''MightyMorphinPowerRangers'' suffer from this. They go from wanting to conquer the Earth to wanting to destroy the Power Rangers, or even simply just ruining their day. Sure, if they get rid of the Rangers, they'll be free to rule the planet, but their plans noticeably go from "This plan will provide us with an unending power source or ultimate weapon that will allow us to take over the Earth" to "This plan will ruin Kimberly's chance at joining the Pan Global Games."

* Morgana from ''Series/{{Merlin}}'' started season three as a vengeful young woman who was out to avenge her own people against the genocide King Uther had committed against those who used magic. Since finding out that [[spoiler: Uther is her biological father]] she's moved from WellIntentionedExtremist territory into flat-out evil, most recently manipulating her best friend's feelings for Prince Arthur (her own [[spoiler: half brother]] who has never done anything to her) in order to try and assassinate her way to the throne of Camelot.
* In the ''Series/LittleHouseOnThePrairie'' episode, "Family Quarrel", Nels and Harriette Oleson have separated and Nels is living in the hotel. Doc Baker and Mr. Hanson get the idea that Mr. Hanson should go ask Harriette out on a date. The reasoning is that Nels will get jealous and will want Harriette back. In the next scene, Hanson is wearing a suit and carrying some flowers as he and Doc Baker walk toward the mercantile store. Doc Baker tells Hanson that now is a good time because Nels is out of town and won't find out. This subverts the original purpose, which was to make Nels jealous.

* In ''[[Series/BattlestarGalacticaClassic Galactica 1980]]'', the episode ''Space Croppers'' begins with the Galactica's fleet being attacked by the Cylons. The Cylons destroy the fleet's food supplies. Boy genius Dr. Zee comes up with a plan to send Troy and Dillon down to Earth to get some supplies. Troy and Dillon pick a farm at random and soon find out that the farmer is having problems with the local growers' association. Instead of picking another farmer to get supplies from, the motive decays into helping this farmer out with his problems and the rest of the episode revolves more around helping a farmer than it does about getting food for Galactica.
* In the ''HighwayToHeaven'' episode ''For the Love of Larry'', a man and his boy are missing. Johnathan and Mark find the dog that was with them when they went missing. The Sheriff runs into Mark and Johnathan and shows them a picture of the missing man and boy with the dog. They explain that they found the dog, which is now in their rented cabin. Instead of asking them to take him to where they ''found'' the dog (as a good place to start looking for the missing man and boy), the sheriff asks them to take him to where the dog is ''now'' and when they find out the dog is missing, they start looking for the dog. The motive decay here is that they stop looking for a man and boy and start searching for the dog while two people are still missing. What was finding the dog going to do?
* The original motivation of Fox Mulder in ''Series/TheXFiles'' was to find his abducted sister. This actually weaves in and out of the story for a good four years, but then it's dropped nearly entirely. When he ''does'' find her, it turns out she was killed, not abducted, and is a ghost child running around a field. What should have been the ultimate climax of the story arc becomes a little sidenote a few years before the series actually ends.
* In an episode of ''TheOffice'' after Michael Scott left the show and Andy Bernard is in charge, Andy is having a family crisis trying to provide for his mother after his father skips town. For some reason that isn't explained in the show, everyone in the office is working on helping Andy with his problem, all on company time and none of them seem to think there's anything wrong with that. Instead of selling paper, they all work on Andy's problem as if it's what they're supposed to be doing.
* In his earliest appearances on TheWildWildWest, Dr. Miguelito Loveless was depicted as a WellIntentionedExtremist, who just wanted to regain part of California, which was stolen from his ancestors (although he was willing to kill over a hundred people to do so) and share his inventions with the world. By the second season, he had become a garden variety MadScientist whose schemes revolved around either conquering the United States [[TakeOverTheWorld or the world, sometimes]] or getting revenge on James West.
* The Borg from Franchise/StarTrek had a small dose of this. Their goal started off as conquering and gaining knowledge. If possible, they would steal technology (most weapons don't work on them or they adapt) and just leave after maybe screwing the other side over a little bit more. Many times they would just destroy enemy ships. They would absorb a being of another species only when they needed information that you couldn't get from a computer (or they needed an ambassador). Come Voyager and the Borg seemed to have "adapted" and are now simply trying to absorb every species, conquering the universe, and stealing technology with absorbing species as the priority instead of as an afterthought.

* In ''Series/{{Babylon5}}'', the heroes defeat [[spoiler:the Vorlons and the Shadows]] by forcing them to acknowledge their Motive Decay. The most damning thing which ultimately convinces them to leave the galaxy is that they don't have [[spoiler:answers to their own Armor Piercing Questions anymore. The Vorlons no longer know who they are, and the Shadows don't know what they want.]]