The horror genre goes hi-tech, this time it's not monsters, a doll or a possessed thing, but a robot! But there is an important lesson that the film wants to convey, good begets good, bad begets bad. As the golden rule says, "do not do unto others, what you don't want others to do unto you". While a robot may just be a piece of machine, in the film it was characterized as something that does have feelings and emotions. It was clearly maltreated by the boy and it somehow transformed into a man-killing machine. While the results of the maltreatment may have led to over the top revenge by the robot, still, in the end viewers are made to realize that, doing something bad to others will ultimately come back to you. What you sow is what you reap.