I've written before that I believe dubs that come in as adults are overly sensitive about the injustice and unfairness in this world. They also have a tremendous desire for justice for those being treated unfairly. They can't accept that the world is what it is. It just "has to get better." (heard this a lot from my JW mother when I was growing up. Still do.)
The WTS exploits those feelings by giving dubs a semblence of "helping" others by selling books and conducting Bible (term used loosely here) studies. The WTS promises that all the injustices will be addressed, sooner or later, by Jehovah. Dubs are so eager to hear this they can't or won't see the WTS's inconsistencies, manipulations, and outright lies.
It's a cult that feeds on dubs with oversensitive consciences by making them believe they're chosen to save the world. I'm talking about sincere dubs here, not the power-hungry elders and others with personal agendas.
I think many adult-converted dubs could have done a lot of good had they not been snared by the WTS.