Some people don't take like to take no for an answer. Some people will continue to engage, despite a woman making it clear that they are not interested; some of those people, however, respect other men enough that they will disengage when they find out a woman is "taken".
And as for the politeness of lying, consider "white lies". Sometimes honesty, even non-brutal honesty, is not the polite option.
And as for the politeness of lying, consider "white lies". Sometimes honesty, even non-brutal honesty, is not the polite option.