The average office worker spends over 30 hours per month in meetings. A significant portion of those meetings did not need to happen. Here is an honest classification.

The Kickoff. A meeting about having other meetings. Involves a deck with a slide called "agenda". Nobody is sure what the deliverable is. Lasts 90 minutes. Could have been a two-paragraph email.

The Alignment Meeting. Called when two people slightly disagree and a manager decides the solution is a meeting with twelve people. Everyone agrees by minute forty because they are hungry. Nothing changes.

The Catch-Up. "Just touching base." This meeting has no agenda. It produces no actions. It does produce a warm feeling of having done something. That feeling evaporates by Tuesday.

The Brainstorm. All ideas are welcome. Some ideas are more welcome than others. The idea the most senior person in the room suggests invariably wins, regardless of merit.

The Debrief. A meeting after the project has ended to discuss what went wrong. The people responsible for what went wrong are in the room. The debrief will not be reflected in the next project.

The Actual Useful Meeting. Exists. Rare. Has a clear agenda, the right people, clear actions and an end time that is respected. Statistically, you attend about three of these per year.

The good news: recognising these patterns is the first step to fixing them. Or at least to making them shorter.