This is about humans.
Many people in the world just do something that they think that it is important, but in fact, those are not important.
They do many things for their advantage and their prestige.
When they die, they cannot bring anything by their soul, so nothing maintain for them.
The only thing that they can leave is their goodness and badness.
It is too late for someone to know every non-sense he/she did before he dies, he want to go back, but cannot.
He want to do good in next time he is born, but he will not remember any failure. So nothing better.
As humans, the only animal which know what is good and can do good, too, so you know what you should do.