The word "no" in English does not translate exactly into, for example, Japanese--not in polite conversation, at any rate. Negative responses are considered impolite, and, thus, must be couched in other terms. One of my favorite books about Japan was one called "Sixteen Ways of Saying No," and, wouldn't you know, one of those sixteen ways was "Yes," which, as often in English, means "I'm listening." The aversion to "no" in this sense is common in Latin American Spanish as well, I believe.
Halvard Johnson