We normal humans tend to be quite envious of the powers possessed by superfolks, but the one we envy most is the power of invulnerability or indestructibility.
That's because we all fear death, and if we knew we couldn't be killed by any normal earthly means we could stop worrying about dying and adopt a devil may care attitude about life.
But being indestructible is not without its drawbacks, and when you live in a world where evil seems to triumph at every turn this power doesn't make you feel any more secure about your place in the world.
And if you end up shooting your mouth off like Deadpool then villains will spend all their time and effort trying to figure out how to make you stay down for good.
It's enough to make you as blue as Doctor Manhattan, who found that immortality breeds apathy and nihilistic tendencies, and Galactus' has learned that immortality leads to soul crushing loneliness.
Of course, it doesn't help that Galactus is older than the Big Bang and has to eat planets to survive, both of which are total deal breakers for most potential dates.