That requires some kind of selection pressure. In the wild, the pressure is that if you can't beat other lifeforms to the good resources, you starve to death/get eaten and don't reproduce. Artificial selection seems like a better model for AI, though. Animals in a factory farm don't have to compete for food, and aren't allowed to control their surroundings in any way. The selection pressure there is that you're only allowed to reproduce if you're tasty and marketable.

With AI and robots, I think the selection pressure is going to be ability to do stuff that (some) humans value, or think they value. The risk isn't that the robots might rebel, it's that the people in charge of them don't understand the consequences of what they're selecting for and/or don't have everyone's best interests at heart.