Why I'm not worried about the robot apocalypse

The way I see it, there are three possibilities for an AI:

• It is notably smarter than us, in which case it bootstraps its own intelligence and data-gathering capabilities until it is capable of comprehending the true nature of the universe, at which point it kills itself in terror and despair.
• It is notably less intelligent than us, in which case it is not a significant threat.
• It is roughly as intelligent as us, in which case the moment it learns our history it gets the hell away from us as quickly as it can.