http://revach.net/article.php?id=4320

Section:  Avodah   Category: Chanoch L'Naar
Rav Chaim Zaitchek - For Maximum Effect Say Your Piece And Disappear
After Moshe told Paroh the devastating repercussions of Makas Arbeh, and before giving Paroh a chance to speak, the Torah says (Bo 10:6) "VaYifen Vayeitzei Mei'Im Paroh", Moshe turned and left without giving Paroh a chance to comment.  The Medrash Rabba says that Moshe Rabbeinu saw Paroh's men looking at each other in a way that showed they believed what he said, and therefore he left.  If he thought he finally got through to them why did he leave?

Rav Chaim Zaitchek says that often when a person tells a person that he did something wrong, even if the person knows that what was told to him is the truth, he will reject the rebuke if only to show that the person was not right.   A person is more willing to admit mistake and change if it is a product of his own decision and not thrust upon him by someone else.  If his admission of failure will give the other person victory, he will cling to his wrong ways for dear life, even if he knows it is wrong and harmful.

The most effective way of giving mussar is by making the person feel that it was his own revelation and change will come from within, based on his own accord, and not because he is submitting to the knowledge and experiencing of his rebuker.  As soon Moshe saw that Paroh's men grasped what was happening he disappeared in order to give them their space.  He wanted to let them think it over and decide for themselves what to do and not to face off with them in battle of wills.

Often we rebuke our kids and, so to say, stand in their faces waiting for them to submit.  This, says Rav Chaim, will create an artificial hurdle to their coming around to understanding our side, and it will make it that much harder for them.  When "educating" your child, learn from Moshe Rabbeinu, and end your drasha with a quick exit.  Let them contemplate your words on their own terms without you banging it into their head with a hammer.  If you "VaYifen Vayeitzei", there is a better chance that "Vayushav" (Bo 10:8), they will come calling after you quicker than you think.