Avengers: Age Of Ultron - 10 Plotholes That Almost Ruin It

Clearly Bruce Banner's decision to send the Hulk away from the Avengers and to try and stop himself unwittingly becoming a weapon for supervillains to use was a pretty sound one. He might not have killed anyone in the African rampage (at least not on screen), but he did cause an almighty bad PR storm, and if VERONICA hadn't been around, who knows what might have happened.

But, when you look back at the end of the film, despite the clash between Banner and Hulk being played up, he's completely in control of the Hulk's dark side when he takes his Quinjet joyride. 

The logic of knowing that he could lose control is present even when he's in monster mode, and while he clearly feels guilty, it's unlikely that circumstances are every going to be so precisely the same as when Wanda controls him in future. That would be like winning the lottery while being hit by lightning. While riding a unicorn.

So exiling himself at that point (or at least the idea that Hulk is now capable of higher cognitive function and moral reasoning) doesn't actually make sense.