There is an interesting story in Telugu folklore which attempts to give reason to Karna getting killed in the Kurukshetra battlefield. The story symbolically suggests that our each of our actions have wide ranging consequences. The story is based on a little girl dropping milk on earth and Karna squeezing it out of earth. This angers earth who takes revenge on Karna.
One day Karna was traveling on his chariot through a village. A little girl who was drinking milk from pot was startled by the noise of the chariot and she dropped the pot of milk. The pot broke and the milk was immediately soaked up by earth.
Karna witnessed this whole event and decided to help the crying girl. He took the moist earth in his hand and squeezed out the milk to a fresh pot. The girl was happy and the people who saw the incident praised the great warrior Karna.
Karna too was happy that he helped the child and basked in the praised showered by the people. He was proud that people realized he was a great warrior.
But earth could not digest this act. She was furious that Karna squeezed milk out her. She swore that at the right opportunity she would take revenge.
She got the opportunity in the battlefield of Kurukshetra. She grabbed the chariot wheel of Karna. Earth squeezed it hard just like Karna squeezed milk out of her. Karna had to get down from the chariot to remove the wheel of chariot from earth.
This distraction gave Arjuna and Krishna the opportunity to kill Karna.
Thus earth too her revenge.
The story from Telugu folklore symbolically explains the results of our actions.
Instead of squeezing milk out of Mother Earth, Karna could have got the girl a new pot of milk. He could have made her happy in numerous other ways. But Karna did something else; to amuse and win the praise of the child and people he squeezed milk out of earth. The whole action of Karna was based on – am a great warrior thought. The action was to win applause, show to the world how a great warrior he was and enjoy the pride associated with it.
Some of our actions have wide ranging consequences. No action is independent. It is the result of a string of actions. Humans have no control over their actions. All that we can do is to follow Dharma and do our actions without any expectations.