The Swan And The Master

It was said that a swan could sing before its death. A man saw a swan on sale and paid for it. 

One day, he was having a meal with his guest. He said to the guest,"Let my swan sing you a song!" 

But the swan did not open its mouth. The master urged the swan to sing for his guest again, but the swan would not sing. At last, he said to himself,"This swan is worthless. I might as well kill it!" 

The swan knew that death was coming and sang sadly. The master was so happy and said to the swan,"I only wanted you to sing. I've no intention of killing you."

Moral 

Know what will motivate a person to perform.