Humans crave clarity in communication. Our brains are wired to seek out certainty, which can sometimes lead to jumping to assumptions. Two key questions to ask (and unfortunately often go unaddressed in meetings/conversations) are:

What is the goal?
What is my role?

Effective conversations tend to begin with someone, usually the facilitator of the meeting or conversation, to express their intention upfront. People want to be helpful in conversations, so if there is a declaration of the goal and someone understands their role in helping achieve the goal, people have better results from their conversations.