In meetings, we get what we allow

We tolerate meetings that don't stay on track because we tell ourselves there is nothing we can do - that we can't interrupt because it would be rude. We also worry that we might be rejected, so we sit through long meetings.

Elon Musk once wrote an email to his staff saying that they should walk out of a meeting if it's evident that they aren't adding value. It's rude to make someone stay and waste time.