Why do ones that got out come back in?
Let's not forget that the "bitter" ones almost certainly have good cause to be.
Why do ones that have faded and been out for years return?
Mostly for reestablishing a relationship with their family members since the WTS blackmails an instructed separation between practicing JWS and not , even to separate and break up families if necessary, which it doesn't concern them.
Protection of their organization is what really counts.
Power corrupts as absolute power corrupts absolutely.
When you have been raised from birth in a cult, you are not given the right education to be able to survive in the outside world as you are kept away from it as much as possible. You are also taught not to trust which puts up a barrier that others can feel. They will then take against you because they sense you are different in some way and social interactions are difficult. I have had much hostility since I left from all kinds of people and its only now I am realizing that much of that is to do with the cult indoctrination. Sometimes this seems to confirm what the JWs teach about the world being a hostile place and there are times I am tempted to run back but then you will get abused in a different way but it is familiar.
There is little help for people who were raised within a cult and so many are trying to cope with a life outside and are having serious problems, some are even taking their own lives because they find it difficult to cope. Its terrible. :-(