Elon Musk founder and CEO of SpaceX has a way of keeping time waste in meetings. former employee of SpaceX posted an A2A on Quora saying that Musk would say something like this:
You haven’t said anything. Why are you in here?
I agree, it's somewhat rude to ask a meeting member to why they're there but borderline it's efficient and in overall less time consuming.
Skyler Shuford, also explains that:
Meetings are expensive. Assuming the fully-encumbered cost of an engineer can be between $80–$100 per hour, having a 10 person meeting can cost a company around $1000 an hour!
References: + : How does Elon Musk run his famously efficient meetings?