OK, so the title is just an idea the society / GB could adopt.
Clearly there is very little growth from outsiders coming into the organization. The ONLY REAL growth is coming from children being born into the faith.
The broadcasts, and the stuff on the official website for children gives proof of the manipulative techniques the GB is using by way of propaganda on these born in young ones.
So, it is not a huge leap to suggest that if the society wants to maintain growth, then they HAVE to encourage witness couples to keep popping out offspring!
No birth control perhaps??