When I was at Intel early on, Andy Grove would famously lock the door at the start of the meeting. The only meeting I was in with him where I saw this in person was an all hands meeting. His argument was that every minute you are late you're incurring many times that many minutes in cost because folks are waiting on you.

I found it remarkably effective. It had the unexpected effect of making meetings end on time as well since folks would not be late for their next meeting. So while I found it somewhat 'quirky' from a culture perspective I had to admit it had a positive effect on time utilization.