Your parents always told you not to lie. Pinocchio scared you into telling the truth because otherwise your nose might grow suggestively. But is lying really all that bad? You can't very well tell someone you're going to kill him and expect him to be okay with it, can you? (As any super-villain knows, you should never explain your evil plan.) Sometimes you just need to lie, and that's okay. In fact, Machiavelli endorses strategic lying in The Prince. Just make sure you don't get caught. P.S. Notice that Machiavelli isn't too concerned with morality and ethics? Yeah, that's kind of groundbreaking when it comes to politics.
According to Machiavelli, being honest is a surefire way to end up without a kingdom.
Machiavelli doesn't write that lying is good in and of itself; it is good only when a ruler needs to lie for the sake of the kingdom.