In the State of Lu, there lived a skilled shoemaker and his wife, a weaver of fine taffeta. One day, they decided to move to the State of Yue to seek their fortune.
Upon hearing their plan, a neighbor warned them, "Do not go. You will never make a living there."
"We don't understand," the couple replied. "We have mastered our crafts. How could we not earn our living? Please don't mock us."
"Indeed, you are skilled," the neighbor explained. "But have you considered that shoes are made for feet, and silk is for hats? The people of Yue go barefoot and wear their hair loose, never using hats. To whom will you sell your shoes and hats? No matter how expert you are, your skills are useless there."
After this explanation, the couple finally understood: any skill, no matter how refined, is impractical if it does not adapt to its environment.