The Bodhisatta was once a royal treasurer and he had a tavern-keeper living under his protection. One day the tavern-keeper left his apprentice in charge of the bar while he went off to bathe. The apprentice saw that the customers liked to eat salt with their snacks so he put some in the grog, ruining the whole batch and angering the customers. After the tavern-keeper told him this story, the Bodhisatta explained that this was an example of how ignorant people who desire to do good end up doing harm.
In the Lifetime of the Buddha
One time Anathapindika, a wealthy supporter of the Buddha, was visiting. He told the Buddha a funny story about his friend, a tavern-keeper. He had once gone to bathe and left his apprentice in change of the busy tavern. The apprentice mixed salt in with the liquor thinking the customers would like it. Of course they didn’t, and when the tavern-keeper returned a short time later there were no customers.
The Buddha told Anathapindika this story so that he knew friend’s barkeeping apprentice had also been a barkeeping apprentice in an earlier birth and had spoiled liquor in exactly the same way.