Obviously, meetings shouldn't be longer than they need to be. But 15-20 minutes of unused time tend to be dead. That's mostly not long enough to do anything useful.
That said, nothing wrong with 30 minute meetings. In my previous analyst stint we tried to default to that--especially for non-clients. Didn't need all the throat-clearing stuff and industry background that we knew perfectly well.
Works best when your meetings are 40 minutes long
Obviously, meetings shouldn't be longer than they need to be. But 15-20 minutes of unused time tend to be dead. That's mostly not long enough to do anything useful.
That said, nothing wrong with 30 minute meetings. In my previous analyst stint we tried to default to that--especially for non-clients. Didn't need all the throat-clearing stuff and industry background that we knew perfectly well.