What is the Moral lesson in parable of the barren fig tree?

The point of the parable for me is that everyone is going to die, just like the Galileans and those at the tower of Silaom. The cause of a person's death is not an indication of whether that person had a relaionship with the Triune God. He was warning people not to make judgments about others' lives but to make sure they changed their minds about who God is and that He has included everyone into his family. The open ending of the parable suggests that Jesus may have wanted his listerners to finish it for themselves.