Why did the bird fall to the ground?

Directions: Read the passage given below carefully and answer the question that follows.

There once was a poor woodcutter. One day while working, he felt tired and sat down under a tree to rest for a while. A little bird flying about happened to see the woodcutter and felt sad at his miserable condition. "I must help him," thought the bird, and perched beside the woodcutter.
As the woodcutter dozed off, the little bird laid a golden egg near him and flew away. When the woodcutter woke up, he was surprised to see the golden egg. He quickly picked it up and slipped it in his pocket. Then he bundled the logs he had chopped that day and carried them to the market.
The woodcutter told the shopkeeper how he had dozed off and found a golden egg when he woke up. The shopkeeper, a cunning man, lured him into exchanging the egg for a single gold coin. The innocent woodcutter accepted. The shopkeeper also told him that if he could bring the bird that laid the golden egg, he could get five gold coins. Promising to bring the bird, the woodcutter went home.
The next day, he went to the same tree where he had found the golden egg and sat down, pretending to sleep. The little bird came again and perched beside him.
Just then, the woodcutter sprang up and caught the bird. "Now I shall sell you to the shopkeeper for five gold coins!" said the woodcutter. "But one golden egg is a hundred times more valuable than five gold coins, don't you know that?" screeched the bird. "The shopkeeper has made a fool of you!"
The woodcutter realized his mistake. "I am sorry I got greedy and harmed you," he said.
But by then the bird had fallen to the ground. "My end is near," she moaned, "I come from the family of Lucky Birds. We bring luck to men, but we are destined to die if ever caught by humans."
The woodcutter heard this and wept bitterly. He asked, "Is there any way I can help you?"
The bird said, "When I die, pluck a feather from my wing and show it to the fire; you'll be transported to my home. Give my feather to my family and tell them the truth." Saying this, the Lucky Bird died.
The woodcutter did as he was told.
In an instant, he found himself amidst the Lucky Bird's family. He showed them the feather and narrated his story to them. "Oh, we must act fast!" said the Father Bird. He kept the Lucky Bird's feather on the ground and began to hop around it. After ten rounds, the Father Bird touched the feather. And lo! The Lucky Bird's lifeless body was transported there.
The Mother Bird and the Sister Birds then brought some green leaves and grass that could raise the dead, and stuffed them into the Lucky Bird's beak. In no time, the Lucky Bird opened her eyes.
The woodcutter was ecstatic to see her alive again. The Lucky Bird then spoke, "Luck appears and disappears; and so do we Lucky Birds. But we don't stay with those who are greedy." The woodcutter cried, "I have lost you because of my foolishness!" "Don’t be disheartened, friend!" said the Lucky Bird.
The woodcutter returned home with a heavy heart, but with the hope that the Lucky Bird would return someday.