Though the witnesses have little clue about this, the generation doctrine works in reality per the Bible.
For one thing, it was not Armageddon that was supposed to occur by the end of that generation, only the second coming and the "end of the gentile times." Note that when Christ takes up kingdom power it's at the same time Satan is kicked down to the earth. He is not immediately destroyed. There is an interim period from when Christ becomes king and "reigns in the midst of his enemies" and the end comes.
But because JWs think Christ arrived in 1914, what else was there to happen but Armageddon before the end of a generation?
But as I stated, their chronology has proven false!! They based 1914 ultimately on the fall of Babylon in 539BCE which they THOUGHT was reliable though they rejected every other piece of evidence to get their own dating to 607BCE and the 20th of Artaxerxes in 455BCE. Turns out we now have critical evidence that explains why there is a discrepancy between the Bible's and secular chronology via the VAT4956 which gives both dates used by the Babylonian-Persians for the reign of Nebuchadnezzar, proving specifically that year 37 originally fell in 511BCE rather than 568BCE. That being the case, the 607BCE and 539BCE dating must be updated. With the 37th year in 511BCE the 19th year falls in 529BCE and thus the true date for the second coming has to be dated to 1992. Of course, 1992, which is near the end of a generation that began in 1914, 80 years after 1914 is 1994, makes more sense per the chronology of the second coming which was really the last event after all those other signs.
The Babylonian text dating year 37 in 511BCE, also coordinates with Biblical prophecy since that dates year 23 to 252BCE which was the last deportation 70 years before the first of Cyrus which must be redated to 455BCE. 455BCE is the critical year that the 70 weeks begins and simply must be the year that the "word goes forth to rebuld Jerusalem" which did occur in the 1st of Cyrus. So now you finally have Biblical and secular harmony once you face up to the fact that the Persians revised their chronology. Fortunately, we not only know for a fact that they did, but we also have a direct reference to what the original dating was, whch limits any speculation beyond that.
If the Messiah was truly dated, therefore, to arrive in 1992 rather than 1914, and the "last generation" began with a world war in 1914, then the prophecy would have been fulfilled since 1992 is 2 years to spare from 1994, 80 years after 1914.
So the witnesses are false prophets, but the Bible is true.
JCanon