2. Loki Thinking He Could Take Over Earth - (The Avengers)
In the words of Thor, "you think this madness will end with your rule?" Good question, Thor, because that was never, ever going to happen. Loki's supposed to be an intelligent guy, yet he thought the pitiful forces of the Chitauri would be enough to overwhelm Earth and its heroes. He'd done his homework, he knew of Iron Man, Hulk, Captain America et al - and he must also have known that Thor would be sent by Odin to stop him - so why did he think that he had even a slight chance of succeeding? He attempted to split the team of Avengers, but failed to acknowledge the basic fact that good people come together in times of crisis. And, given that his tactics seemed to be as Neanderthalic as "destroy and kill everything in sight", what exactly did he hope to rule at the end of it all, even if the fight had been successful? Essentially, the whole plan was incredibly poorly thought out and to think that he, alongside a hapless group of Chitauri soldiers, stood a chance against Earth and the Avengers was very naive.