A crow, on the verge of dying with thirst, saw a pitcher in the distance and flew to it with joy. But when he arrived, he discovered to his grief that it contained so little water that he couldn’t possibly get at it, despite all his efforts. At one point he decided to turn the pitcher over and break it. However, he was not strong enough to succeed. At last, seeing some small pebbles nearby, he gathered them and dropped them into the pitcher one by one. By this means, the water gradually rose tothe brim, and he could quench his thirst with ease.
Old Learning: Necessity is the mother of invention.
Trying only can lead to success. Losing hope and giving up ensures it doesn’t happen.