It's like any organization, once it's been established the goal is to survive, to maintain itself. Of course any organization is a group of individuals, and they are what keeps the organization going. Individuals may start out as true believers, but I think once you become part of an organization hierarchy in a corrupt religion like the Watchtower two things come into play. 1) people have a hard time facing the fact that they made a bad choice and 2) People become invested in maintaining their position.
It's a normal behavior for people to continue to justify bad choices rather than admit they made a mistake. Study after study shows that rather than abandon a course of action when it doesn't work out, people are likely to invest even more time energy or money in is a course of action. The ego is fragile, people simply cannot admit they were wrong. People like Barbara Anderson, who courageously spoke out when she saw things were not right are very rare.
Then, when people become part of the hierarchy in a corrupt religion like the Watchtower they become invested in maintaining their position, they become corrupted themselves. I think that is why people remain, even when they find out disturbing information. You may fool yourself that you are still a believer, but at some point you have sold out and you know it. It doesn't matter than its an unpaid position, you are getting room and board at the least, security, some status and to leave would be difficult, the higher you go the more difficult it is. Can you imsgine someone on the GB leaving and becoming a regular person again? What are they going to do, be a Wal-Mart Greeter? If they had an ounce of integrity they wouldn't be where they are, it's never going to happen.
We had a hospital services district (a government organization) in a nearby town that effectively served no function, there were no hospitals in the town, nor had there been for years. None of the people serving had any motivation to petition to dissolve the organization because they were getting a paycheck for virtually no work. It became a self licking ice cream cone.
That is why you are seeing desperation on the part of the governing body. They see the problems, but at this point it's impossible to be honest and admit the organization was ever wrong, or they were wrong for staying, and they will never change course in any substantial way. They simply double down on the stupidity and hope things get better, they have no choice. And the organization may start to shrink, but there will always be believers, no matter how big the problems get, because they cannot admit they were wrong either.