Why Die?

I don't think we should all die.  I know that might sound strange at first, but I've been thinking about it and I really don't think it makes much sense to die.  Like, you know how after you get cut or something, your body slowly fixes it and makes it all better.  Well, why would your body intentionally replace itself with crappy parts.  Old people parts.  I think that sucks.  I think cake is kinda overrated too.