I was reading a book the other day, it was historical fiction, but took place during the time of the Millerites, a group following William Miller. The believed based on some chronology he pulled out of his rear that the end was coming in 1843. People actually didn't bother bringing in the crops or milking the cows, they went up on the roof of their barn and waited for the end. At the end of the night they sheepishly got down and went on with their lives.
The millerites did not give up, they then explained that Christ had come invisibly (sound familiar?) Various factions come up with alternate theories and new dates, one group becoming the Seventh Day adventists, and of course CT Russel browsed heavily from them for his own special end time predictions. The bible states quite cleary that no one knows the day or the hour, so anyone making any prediction is going against the scriptures, but they just keep doing it because fear is useful to manipulate people. The more things change, the more they remain the same. It's a con game that has been going on for a while.
It made me realize that I was just as foolish as those people standing on the roof of their barn. It's hard thing to have to admit you were wrong, but the alternative is to remain in ignorance, afraid to see reality.