If one pounds a brick wall with a sledgehammer often enough, the wall WILL crumble. How do we get through to stubborn people enough so that their obstinacy crumbles?
Stubborn people many times have a hard time admitting they are wrong about *anything*. Relentless pushing will do very little to get them to budge. Good solid information backing up your claims or desires will help make your case, and it can all be in how you deliver the message sometimes to. I like to start by saying “I see your point, but if you consider these other points you may see things a bit differently” or something similar that is non-confrontational. Otherwise a good swift whack up the side of the head with a bag of frozen peas will get their attention.