Why do we build graves? To serve as guardian deities for those left behind.
People who have a connection with a person come to visit their grave. Those who say, "I was all alone in the world, so no one will come to visit me," end up with many people coming to visit later. This is because they have helped others without realizing it, and these people come to visit their graves thinking of them.
Whether or not you visit the grave is up to those left behind, but as a deceased person, you have a responsibility to create an environment for those people to visit the grave.
Why do people who are related to the deceased visit the grave of their loved one? They come to introspect themselves by facing the deceased.
Therefore, when all those who are connected to the grave have reached paradise, the grave's role as a guardian deity will be completed. When it has fulfilled its role, the grave will become just a "stone." We should not think of it as a "stone" and become more attached to it than necessary.
The above explanation is based on the assumption that you will build a grave for yourself and be buried there. The rest should be understood as the difference in your position relative to the grave.
Leaving one's own fragrance remaining as a guardian deity means preserving an environment for those left behind in which to reflect on themselves.
Ossuary
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