I am only speaking from my personal point of view and not to encroach on anyone else's belief system:
One of the main points of attraction to the JW life was the 'Panda Paradise', once I woke up, I began to think about the future and it made me realize that JW's have little or no regard for life and the way they treat others even in those who are JW's.
e.g. No Blood, Shunning, Theocratic Warfare, No real charity work for those in need, etc...
If we live forever on earth we would get bored, we would take relationships for granted and possible want to actually die.
What makes anything valuable is the not the beauty of it but the rarity of it or the limited amount of it.
Time is not only limited but all of our hourglasses are opaque leaving the amount of sand remaining a guess at best, and this is what moves us to appreciate life and ever little thing it gives us.
There is a beautiful and poignant song by Jason Isbell 'If We Were Vampires' and it perfectly describes the beauty one can find in ones mortality and how it moves us to Love & Care Deeper than if we were immortal.
The 2nd verse goes
If we were vampires and death was a joke
We'd go out on the sidewalk and smoke
And laugh at all the lovers and their plans
I wouldn't feel the need to hold your hand
Maybe time running out is a gift
I'll work hard 'til the end of my shift
And give you every second I can find
And hope it isn't me who's left behind
Country may not be your thing but if you want to hear the song: