Immortality. What a great thing, you'll say. It would be awesome to never die, whatever happens. Juggle with knives without any risk, you will wound yourself in the worst case, but wounds are forgotten. Go out in the snow without clothes, you'll get sick, but take an aspirine, and sickness's gone. So, you say, immortality is great. You're wrong. Imagine to never die: you'll see everyone you love grow, become old, and die, while you couldn't die for erase this pain. You'll see your son, and their son: but everyone will go, while you'll remain alone, without anyone. Yes, you'll experience all of the reliefs, but all of the pains too, and trust me, they're way more. You'll wish to die, but this relief will not be granted to you. You should remain alone, until the Sun, the Earth, everything will cease to exist.
You'll know pain in every aspect