The great Sri Dhammananda told a story:
A great Indian sage, Venerable Dipankara, was invited to Tibet to teach. He brought with him a quarrelsome, irreseponsible and bad cook. After observing for some time, the Tibetans respectfully approached and said, "Master, why do you tolerate this useless cook of yours? He is more of a nuisance than a help. We would gladly tend to your needs."
The Master smiled and replied, "You don't understand, I do not keep him as my servant, but as my teacher."
The Tibetans were surprised and asked, "How is this so?"
The master explained, "You see, his inefficiency and quarrelsome nature teach me to practice patience and tolerance everyday, therefore, I value him."