I recall reading several years ago that many Americans believe that if they have to devote more than ten minutes to preparing a meal, then they have engaged in serious cooking. As a result, the frozen food companies try their best to keep preparation time below that magic number.
This makes me wonder "How long is too long?" when it comes to the workplace. Here's a rough - and completely arbitrary - guide:
Routine staff meeting: A 15 minute length should be the maximum. Limit time and you force people to get to the point.
Brainstorming a specific topic: No more than two hours and that's being generous. If people are experiencing brain-lock, reconvene at another time.
Board meetings: Lean agenda, one hour. Packed agenda, two hours. Let it drag on and the caliber of discussion will decline. [Sometimes you have to indulge the ego. As Congressman Morris Udall once noted, "Everything has been said but not everyone has said it."]
Face to face employment interview: At least one hour unless all the candidate has to do to demonstrate his or her skills is to fog a mirror. Don't go beyond 90 minutes.
Termination meeting: No more than 30 minutes. You're there to deliver a message, not to discuss a decision, and once that message has been delivered, the recipient would rather be somewhere else.