Taking Matters

If you want something done, you have to do it yourself. In other words, there comes a time in a story when the villain decides enough is enough and it is time for him to take matters into his own hands and carry out his evil plan himself. This usually happens under these circumstances: This can lead to a villainous breakdown, crossing the Moral Event Horizon, and/or the final showdown with the hero.
 * The villain is running out of time and/or reaching his/her deadline.
 * His minions fail to carry out his plans.
 * His army is defeated in battle.
 * He discovers an opportunity.
 * The villain's plans (usually constantly) fail.
 * The villain reaches his breaking point.

Examples

 * Thanos: After Loki Laufeyson failed to conquer the Earth with his scepter and Ronan betrayed him he donned the Infinity Gauntlet, deciding he will gather the Infinity Stones himself.
 * Queen Narissa decides to poison Giselle herself after Nathaniel fails to carry out her plan.
 * Thrax takes matters into his own hands when his deadline is approaching to kill Frank.
 * The Wicked Queen decides to take matters into her own hands and kill Snow White herself when the Huntsman defies her and brings back the heart of a pig instead as she goes to the Dwarfs' cottage, disguised as a witch-like peddler.
 * After his robot probe is destroyed, Gallaxhar decides to capture Ginormica himself and obtain the quantonium.
 * After realizing that Cady Heron gave her a weight loss bar, Regina George decides to get her revenge and turn the school against each other herself.
 * Ursula takes matters into her own hands and prevent Ariel's romance with the human prince Eric when the third day - the day Ariel has to kiss Eric - approaches.
 * Judge Doom deciding to kill Eddie Valiant himself after weasels failed that in to kill him.
 * Governor Ratcliffe makes his decision to shoot Chief Powhatan himself when the colonists defy him.
 * After noticing that Ofelia has made off with his newborn son, Captain Vidal decides to go after the girl and kill her himself.
 * After his henchmen are overpowered by Gutsy and his force, General von Talon decides to go after Valiant himself.
 * Colonel Richard Strickland makes his decision to go after the Asset after interrogating Zelda.
 * After Chris Bradford and Xever have failed to eliminate the Turtles, Shredder announces that he will deal with them himself.
 * Nigel: Upon seeing that the marmosets failed to capture Blu and Jewel (and got the living tar beaten out of them), Nigel decides to take matters into his own wings and find and retrieve the macaws himself.
 * After the dark forces failed to kill Anya while she's on her way to Paris, Rasputin decided to kill her himself in person.
 * Sōsuke Aizen: Aizen seemingly killed his lieutenant Momo Hinamori himself after his former lieutenant Gin Ichimaru failed to kill her while fighting Tōshirō Hitsugaya.