The question from this one is psychologically contrasted with the question from this manga:
https://mangadex.org/title/22440/jumyou-wo-kaitotte-moratta-ichinen-ni-tsuki-ichimanen-de
You can buy Immortality with literally anything.
You can sell your life to earn some interest.
One has thrown out his wish to be immortal because of the friendship, for no one would be sad, even though the place was supposed to be "sad".
One has lived without a single bit of happiness until he sold his life for 10000 yen a year, then ended up happily with his last 3 days. (that's why it has an alternated name 3 Days Of Happiness, and guess the spoiler tag was right, after all).
And one other, who would state that if immortality was a skill, then everyone would try and take it for them.
But would Immortality really makes your life better?
After a bunch of events and memories, you would no longer respect or even call them by their usual name. You won't even know what is happy, anymore.
You lived for so long you can be happy whenever you want.
(sorry for the guys who would sell their life first then buy the immortality later that, but it really goes the exact same trail.)
What I want to tell here is to take a deep thought. We respect the best bits of our life because it is limited.
The best feeling to leave the world was the one with memories of happiness. The legends, the famous, they all leave to show how beautiful life can be when it is limited.
