I’m sure we all have one person in our lives that never lets us finish a story. They might even ask us a question and expect an answer. But they interrupt us for their own tale long before our own story is finished.
My stories are never that important (well, at least to her they aren’t), so it doesn’t make much difference. But what if your main character has information another person needs to know and every time they speak, the other person interrupts? Do they tell the other person to shut up? Do things on their own? Wait until the situation falls apart and let the other person know that if they’d listened, maybe they could have come up with a solution (ooh, so passive/aggressive)?