Most people assume that they would be in the bloom of their youth if they had immortality. They think they would have their healthy 25-year-old body but with the benefit of years of wisdom.
What if you had to live forever with a broken down elderly body.
You couldn't hear, you couldn't see, you couldn't remember anything, you soiled yourself, you couldn't take care of yourself.
And you couldn't die.
You were going to live forever.
That would suck.