That means that two-thirds of the people who told Pew they were raised Jehovah's Witnesses no longer are — yet the group attracts roughly the same number of converts.
Was that a necessarily 'bad' thing though from the JWs point-of-view?
The problem is that those who are 'born-in' become JWs by 'default' having made no real decision and are more likely to be 'weak' members.
Whereas those who have converted have made a specific decision to join and are therefore more likely to be 'stronger' members.
Of course the problem the JWs DO have. now. Is the lack of converts combined with born-ins leaving.