No Honor Among Thieves

In order for a team to be effective, teamwork and trust among members is needed. Villains on the other hand, who are often motivated by greed or power rarely (if ever) trust each other. As a result, it is common for villainous teams and evil organizations to ultimately destroy themselves from infighting. This can take several forms.
 * The second in command tries to kill or usurp the leader in order to seize power and control.
 * A member of a heist team in a heist that has gone wrong abandons their companions with as much of the stolen loot as they can.
 * Thieves start fighting over larger quantities of stolen loot instead of dividing it equally.
 * Multiple major villains in an alliance or team-up start fighting among each other when victory is near.
 * Unruly vassals or governors in an evil empire, kingdom or nation tries expanding the power and influence of their own territories and fiefdoms at the cost of the others.
 * A boss betrays a high ranking minion when they are of no further use for them
 * A villain betrays another because they were paid to do so by another evil party

Examples

 * Madame Medusa betrays Mr. Snoops as soon as the Devil's Eye diamond is in her possession hoping to make more money rather than split the loot with him. Snoops in turn betrays Medusa and the two start fighting over the diamond while Penny escapes with Bernard and Bianca.
 * Diablo, Mephisto and Beal have at times succeeded in assaulting Heaven, but every time victory is near, the demon brothers start fighting among each other for greater power, this allows the Angels to launch a united counter attack and defeat the demons.
 * Starscream has attempted to overthrow Megatron and become leader of the Decepticons at least once in every incarnation of Transformers except for maybe the live-action films themselves. The only mention of this is when Megatron berated Starscream for leaving him "for dead" in Revenge of the Fallen, and later when Megatron refers to Starscream's decapitated head as his "treacherous friend" in The Last Knight.
 * Marluxia and Larxene attempted to overthrow Xemnas and seize control of Organization XIII by trying to take control over Sora.
 * Ramsay Bolton betrays his father Roose Bolton in order to seize control of The North.
 * In the post-Revenge of the Fallen Titan Magazine comics, Bludgeon murders fellow Decepticon Breakdownin order to ensure discipline to the Decepticons of his splinter faction.
 * In the Rising Storm comic prequel to Dark of the Moon, he mistakenly kills Storm Surge while fighting against Mirage yet does not seem bothered by it.
 * Preed betrays Captain Korso and holds him, Cale, and Akima at gunpoint in order to save his own hide from the Drej.
 * Darrell Boxman rats out Lord Boxman on Cosma, getting his father fired and launched out of a cannon towards the sun for the destruction of Box More caused by Boxman Jr. and ultimately taking his place as company CEO out of jealousy for Junior.
 * In Transformers: Requiem of the Wreckers, Overload double-crosses Tarantulas by revealing that he intends to use the Timemaze to kill Megatron throughout all of time and space.
 * In a twist of the Moral Event Horizon, Kylo Ren murders Supreme Leader Snoke and assumes command of the First Order because he wants to "let the past die".
 * In the 2016 Ratchet & Clank film and PlayStation 4 videogame, Chairman Drek gets turned into a sheep by Dr. Nefarious and is sent to New Quartu in an escape shuttle while the "vengeful scientist" commandeers the Deplanitizer.
 * In the second season finale to Robots in Disguise, Steeljaw acquires a pair of Decepticon Hunters and uses them to take control of "Decepticon Island", the wreckage of the starship Alchemor. When Glowstrike tries to fight back with a similar weapon left behind by Bumblebee, she and Saberhorn are incapacitated by Steeljaw.
 * In Teenage Mutant Ninja Turtles: Out of the Shadows, Shredder has Baxter Stockman sent to Tokyo upon revealing that the scientist has only been "a footnote". However, Shredder himself is betrayed by Krang, who was using him to open a portal to Dimension X for the Technodrome to emerge through.
 * Over the course of the Ben 10 franchise, Vilgax has been known to double-cross other villains such as Albedo, Eon, Dr. Animo, and the Weatherheads if it means getting the power of the Omnitrix for himself. In the end, Vilgax gets fates worse then death: getting his butt kicked by the very villain(s) be was using. This is especially seen when he gets sent to the Null Void by the High Override following a failed attempt to betray Ben and Glitch and take over the Omnitrix during the Fulumni invasion.
 * Similarly, Khyber left Dr. Psychobos to be captured and abandoned both Zeb and his Panuncian on two separate occasions, having retrieved the Nemetrix in the process. Khyber would get his retribution when Skurd defects to Ben's side, leaving the bounty hunter to uncontrollably transform into Tyrannopede before finally being robbed of the Nemetrix and taken into custody.
 * Additionally, Maltruant double-crossed his lackies, resulting in Psychobos being left behind in Mad Ben's dimension, Subdora and Exo-Skull being left in Ben 10,000's timeline, and Eon getting banished back to his home dimension. In the end, this left him with no one to prevent him from being imprisoned in a time loop of getting destroyed and rebuilt again and again for an eternity.