We don't know what the future holds for us

After conquering the world, Sikander was looking for a kind of water, which would make him immortal after he drank it.

After much wandering in the world for a long time, Sikander eventually found that place, where he could get nectar.

He entered the cave, where there was a waterfall of nectar. He became joyful. 

He was inclined to drink with the nectar in Anjali, when a crow who was sitting inside the cave, said loudly, 'Wait, stop, do not drink it.'

Sikander looked towards the crow. The Crow was in a state of great misery. The feathers had fallen, the paws had fallen, also had become blind. 

Sikander said, 'Why R u stopping me ?'

Crows replied, 'Listen to my story. I was looking for the same water so that I would also become immortal.  I drank this nectar and Now I can not die, but I want to die now. See my condition I have become blind, feathers have fallen, I can't even fly. 

 Once you reflect on my condition , then only decide to drink Amrit. I have been screaming so that someone can kill me, but nobody can help me.

Now praying to God that the Lord kills me. The only desire is to die in some way.

Sikander reflected. Then quietly returned out of the cave, without nectar

Sikander had understood that the happiness of life remains till that time, as long as he was in a position to enjoy that happiness.

So Enjoy each and every moment. We don't know what the future holds for us.