Why Do People Do Bad Things?

A question that has troubled humankind for as long as we've been able to formulate it, no doubt.

Let us consider a moral agent, Agent Q. (Not 007, no.)
Q commits an immoral act B (B for bad. Or maybe for /b/.).

Possibilities:

1. Q performs B because she doesn't know any better. She may have no conception or understanding of morality, or at least not the required kind of morality at hand here. Perhaps she is an animal or mindless drone and not a moral agent at all.
   
2. Q performs B but does not believe it is wrong. This is basically a variation of 2, only now I assume Q does understand why other people might think B is wrong, yet she disagrees. Maybe she's Nietzsche.
   
3. Q believes that B is wrong, yet she wants to benefit from B (in whatever way she does) badly enough to overcome any moral hestitations. She could be Judas, I suppose.
   
4. Q believes that B is wrong and does not think that B's selfish good will outweigh the evil it entails. Somehow, Q performs B nonetheless. Q now seems to be conflicted – was this a lapse of will (akrasia?) How do we account for what has happened? Did Q choose to do B? Why, when she knows that it's wrong?
   
5. Q had no genuine control over her actions.
   

The real one we're concerned with is naturally number 4. Why do I do (or does anyone) do that which disagrees with her own judgment?

Are we simply animals? Do we have impossible standards?
What gives here.