Equally strange that so few of the people who believed a false prophecy can admit that it was wrong when it fails to come true.
It seems strange but it comes back to the philosophical problem of identifying truth . . .
If you take for example C T Russells rather quaint illustration of truth (in Barbs post) being like a "modest little flower in the wilderness of life" . . . it doesn't confront the question of "what is a flower?" . . . To identify a flower one must have a pre-conception of what a flower is . . . as opposed to a weed. There is no answer for this, as some degree of objectivity is required. It can only ever be . . . "I consider this a flower because it fit's my idea of what a flower should be . . . and resembles other flowers I have seen. It still ignores the fact that one man's flower may be another man's weed.
Therefore the problem with declaring a truth, is that the individual becomes his own subjective judge in the matter. Religionists, including the Watchtower Society assume the role of doing this judging for others . . . so they see themselves as the "botanical authorities" on matters of truth. Identifying "flowers" becomes their preserve, and admission of error undermines that authority. Therefore such an admission is never forthcoming. As their flowers turn into weeds . . . they simply pick more flowers and say . . . "Look! . . . a flower!" . . . thus maintaining the illusion of "botanical authority" Onlookers will say "Yes it is indeed beautiful". It is this illusion which allows them to continue as james_woods says . . .
truth changes when we tell you it changes.
They spend the whole time picking flowers . . . they're not interested in weeds.
I'll stop before I cease making sense.