Look (or remember) around at the next convention or assembly. The halls and auditoriums are filled with couples in their 70's and 80's - at least here in America. The great majority of these older folks came into 'the truth' during the 1960's and 70's. When their children bury these parents (with dreams of never dying) they will stop attending. The grandchildren of these older ones may be baptized as young Jehovah's Witness children - but they are mentally out or 'inactive'; going through the motions as good JW kids.
Membership is not increasing through proselytizing. The quantity of raised in/born in Jehovah's Witnesses that remain active is shrinking. It's just a matter of time.
Unless....a scandal comes to light. A scandal from within that causes many to lose their faith in the Organization. A scandal so powerful and public that the Watchtower and it's Governing Body loses it's role as mankind's source for salvation in the eyes of the current faithful.
It's just a matter of time.
ginger