If your a Jehovah's witness what false prophecy would you say affects you the most that watchtower said? maybe it can be some of the teachings they changed?

If your someone who was a JW and left what would you say was the worst false prophecy ?

those who never were a jehovah's witness what do you think is one of the prophecies do you think was the worst?
Vot seems your a Christian so I would have to assume your believe you need to be born again as it says in John 3