This is true. From the word itself, the main goal of a persuasive speech is to capture the hearts and opinions of the readers and make them agree to yours. So, you always start off by relating to what the majority accepts. Then, slowly you present your own opinions. You don't have to be right all the time because it would irritate the readers. It is important that you present moments where you are right and they are wrong, and when you are wrong and they are right. In the end, you may end up with a compromise.
