For one, AI's don't have common sense nor any way to obtain it, because they aren't out in the world as humans are, learning all the large and small details that can't typically be found on the web. The Myth of Artificial Intelligence: Why Computers Can’t Think the Way We Do is a good reference for more details.

For another, AI's don't have human (or any) biology and thus don't have organic feelings, which means among other things that AI's do not have empathy.

AI's will naturally be prone to the kinds of behavior that characterize human psychopaths for that reason. Smart, maybe -- in narrowly defined areas. Compassionate? Empathic? "Does not compute." Attempts will (and are being) made to simulate empathy and compassion, but I wouldn't want to bet my life on them.