I take a more moderate view of this issue. I agree with the indications of psychopathic personality, but I disagree with the motivation for it. Religion is only about power for a few. Most people are attracted to religion for the same reason they are attracted to a certain political party, and more broadly it's the same reason why they root for a sports team or invest in popular stocks; it's about security. It makes people feel safer to be in a group, and on top of the emotional satisfaction that comes from tribalism, religion can provide answers (intellectual satisfaction) for the problems in our lives.
I think that the people at the top, i.e. the GB, have gotten good at ignoring their consciences (a sociopathic indicator), but they still believe on some level that they are perpetuating something good, albeit flawed, that serves an important purpose. They see the flaws in the teachings, but they still believe they are closest to the truth! Some may even be more jaded, and believe that they aren't closer to the truth than some other groups, but nevertheless God chose them as his representatives so they need to keep doing what they are doing, and hopefully improve the doctrine a bit more as they go. Keep in mind that these are people who (unless they are flat-out lying) genuinely believe that God anointed them with holy spirit. They therefore extend that dogmatic certainty to the organization as a whole -- "we are chosen, therefore this org. must be chosen".
Psychological studies* have shown that the majority of humans will engage in cruel behavior, not for personal gain, but in the name of following orders. Whether those orders come from other men, or (so they believe) from God, makes little difference.
*I think we all know about the infamous Stanford prison experiment. Although there are valid criticisms of its results, if one reads the details of the experiment and its criticisms, I think you'll find that the results are applicable to the Witness religion. Other experiments mentioned in the WP article have partially confirmed Zimbardo's results, so I'm comfortable saying "studies", plural, in the above statement. This is probably deserving of a separate thread if there isn't one already.