Personal observation: Over the years I have noticed a pretty accurate success/failure indicator. Was your meeting successful? One indicator of success or failure is the amount of time the meeting holds together. How fast people move out. How many people remain after the meeting is dismissed.

When a meeting is successful people tend to stick around and talk, conversely when a meeting is a flat out failure it breaks up fast. When a meeting is a looser people tend to split for home even before it ends. Encourage your people to stick around afterwards.