Those are cultural habits that can be broken. Start meetings on time, don't let people straggle in. Setting half hour meetings is easy. For my part I'd love it

Those are cultural habits that can be broken. Start meetings on time, don't let people straggle in. Setting half hour meetings is easy. For my part I'd love it if more people would accept 20 minutes as a reasonable meeting duration, but it definitely requires companywide norms to get people to fragment their calendars that way.