Basically because they feel they are not being blessed.
I don't think they were ever really "blessed". Here it is over a hundred years later and they still haven't spread the word world wide even though television and radio cold have done the job decades ago. They wouldn't have had to have factories, printing presses and thousands of Bethelites if they'd have used their funds in those mediums to spread the word instead of printing endless books.
What's happening now is people are daring to question and it's easy for them to verify the information they are getting, from the privacy of their own homes. A tighter hold is needed to stop them from doing that. At the same time, they need to get off their horse and make being a JW more doable for today's world.