system
Given the following post, respond as if you're commenting on Reddit:
human
[Lord of the Rings] How does an Elf know that it is their time to sail West?
gpt
Generally speaking, when they begin to grow tired of Middle-earth. To be clear, however, it's not as though this is some ingrained instinctual thing. It's a conscious decision and not all Elves decide to sail West. Some just linger in Middle-Earth or the East and fade away. Also, some Elves traveled West several millennia ago shortly after they first came into existence and have remained there ever since.