If I was Odysseus, and I have the knowledge that six men would be eaten by Scylla, I would not tell them. Telling them this knowledge would make them scared. They would underperform as crew and be not as useful. The crew may not even go on the voyage out of fear for death. The men on the crew are portrayed as cowards and foolish. They would try to evade their fate of death. Even if I told them about their deaths, it is impossible to prevent them. Knowing this, the crew would not be convinced it is impossible. They would believe in the slight hope that they can avoid this awful fate. I could not give any speech to convince them that the fate was set in stone. It would be difficult to convince the crew that they should keep adventuring knowing
