The strongest argument can still fail if nobody feels heard enough to consider it.

Being right is not sufficient. A person who does not feel heard will not consider your argument no matter how sound it is, because their attention is occupied with not having been understood. Making them feel heard is not a tactic; it is the precondition for anything you say being processed at all.

Before making your case, put their position into words well enough that they would agree with your version. Then ask if you got it right. Only after that make your argument. It takes longer and it is frequently the difference between being correct and being persuasive.