http://www.expertlaw.com/library/investigators/serial_killers.html#4
5. Victim Objectification
As a serial killer steps away from his base, whatever it may be, to begin the hunt for human prey, it is almost always true that he knows absolutely nothing about the person who is fated to become his victim. This is true even in the case of such serial killers as William Lee NEAL- Colorado, who cultivated his victims over lengthy periods (acquiring their possessions as well as their trust) before finally and viciously ending their lives. But for him as well, each future victim began as a stranger about whom he knew nothing. In this way does a serial killer differ from a man who, in a burst of anger, kills his adulterous wife, as well as the cold-blooded planner who kills for revenge?
It may be that having no prior knowledge of a future victim further enables the process of that victim's objectification. For as far as he is concerned, his next victim is not even a human being, in the accepted sense. So, well before he ever crosses paths with his next victim, he has already stripped that person of all human meaning and worth; he has unilaterally decreed from afar that the person is deserving of no human consideration whatsoever.
Thus, then, in a serial killer's perception of his victims; past and future: that each is nothing more than an object, depersonalized in advance, existing only for himself and his enjoyment, and solely to be seized and used as he sees fit. Moreover, he perceives his unseen prey not just as an object to be used, but as an object unworthy of any consideration, worthy only of extreme contempt, vicious abuse, and ultimate destruction.