A very good question Stephane and an excellent reply Bennyk.
A big lie to demonstrate your point; from the 1950s or perhaps a bit later the slogan was that the generation which saw 1914 would also see the end of the "old system of things". The same lie for three generations during which time this carrot was dangled to the Watchtower donkeys who gave up their right to their own choice of life-style and served the Watchtower in mind word and deed. They never saw the promised reward, no because a Jehovah's Witness never does-- however the organisation became very rich by offering this false lure.
I do find it almost impossible to find anything at all which the JW org has said which is actually true and useful to know. Virtually everything they say turns out to be false, a false hope. Whatever they say, preach or indicate will happen it is not worth believing or putting faith in since it is either plain wrong or it is sooner or later replaced with another dodgy belief which also has no practical value in knowing it.
If you value freedom and sound reason: do not listen to Jehovah's Witnesses!
Everything the JW org says is useless except for the purpose of HQ controlling the minds of their dumb followers.