It's quite easy to break down what Musk's warning us about: the technological singularity.
The reason the word "Singularity" was coined for AI is exactly the same reason we use it for Black Holes, where our mathematics breaks down and we have absolutely no idea and can't know what happens beyond the event horizon of a black hole.
With AI, the same thing is facing us. We have no idea nor can we even guess what happens after. We have zero reference points to call upon nor can we even begin to calculate what will/may happen.
Given: an AI is switched on and immediately starts improving itself exponentially. Hits an IQ of, say, 10'000 within a week of going "live" (i.e. what is called the
Intelligence Explosion). How will we mere mortals even begin to understand what it's thinking? What are its morals (if it even has morals)? What are its aspirations? What values will it have? How will it perceive humanity? And so on.
In other words, we're rushing headlong into completely uncharted and unknowable territory. Let no one fool you. We have no idea of the capabilities that a "conscience" AI may entail. None whatsoever. A good starting point to try and understand what we'll be facing to read
Nick Bostrom's "Superintelligence: Paths, Dangers, Strategies" or watch one of his Ted Talks like this one: "
What happens when our computers get smarter than we are?".
As Arthur C. Clarke once said, "Any sufficiently advanced technology is indistinguishable from magic".
In other words, we most probably have no frigging clue of what's going on.
Our last invention.
And for those who find the robot "hot", just wait a couple more years, if we don't become batteries for the AI.
Dawn of the sexbots