"A friend of mine rarely does anything the first time someone asks him. He knows that people sometimes ask for things that they turn out not to want. To avoid wasting his time, he waits till the third or fourth time he's asked to do something; by then, whoever's asking him may be fairly annoyed, but at least they probably really do want whatever they're asking for." -- Paul Graham, "Being Popular" (an essay about designing programming languages.
(It's Paul Graham week in my Quote-of-the-Day file.)