Once upon a time, a fox set out from his house to meet a friend. The sun was shining in full glory and it was very hot. Even the ground was scorching and the fox was finding it difficult to walk in the heat. But nevertheless, he continued to walk with the assumption that he would find food and water on the way. After travelling for quite some time, the fox was unable to find neither food nor water and was so dejected that he thought now it would have been better if he had stayed back at home.
Then the fox saw something dazzling in the sunlight. It was a bunch of grapes hanging in front of him. As soon as his eyes fell on the grapes, he thought of how sweet and delicious they would be if he was able to devour them. With this thought, he started leaping into the air and tried to pluck the grapes. But the grapes were too high for the fox to reach. The fox jumped and jumped, over and over again, but he could not reach the grapes no matter what he tried.
The fox was completely exhausted and he finally decided to walk away. He was upset and tired and very much frustrated about not being able to get the grapes. So, in order to pacify himself, he spoke to himself and said that the grapes would not be as sweet as he thought. They would be sour and hence would not be delicious. Saying this to himself repeatedly, he moved on from the spot and continued to walk towards his friend.
Moral - A bad workman blames his tools. It means that a person who fails at something, will always find something or someone else to blame.