A businessman was highly critical of his competitors' storefront windows. "Why, they are the dirtiest windows in town," he claimed. Fellow business people grew tired of the man's continual criticism and nitpicking comments about the windows. One day over coffee, the businessman carried the subject just too far.
Before leaving, a fellow store owner suggested the man get his own windows washed. He followed the advice, and the next day at coffee, he exclaimed, "I can't believe it. As soon as I washed my windows, my competitor must have cleaned his too. You should see them shine."
Confucius once declared, "Don't complain about the snow on your neighbor's roof when your own doorstep is unclean."