When smoker lights another cigarette from the one they are already smoking, we call it chain-smoking. A similar phenomenon occurs in meetings. I'm sure you've seen it...

Bob asks a question and discussion begins. The discussion stimulates Sarah to pose another question, so she does. This question and the ensuing discussion causes Brian to think of an unanswered question he has about a related, but different problem.

Unless someone is recording this meeting as a brainstorming session, it has descended into a more or less chaotic group event. This can be very costly.

Organizations have meetings to accomplish specific goals (or they should). These goals usually don't include having a room full of people satisfy their curiosity. Chain-questions cause rapid subject shifts, which lose some of the listeners and perhaps even the meeting organizer. The effect can be that attendees get a mental version of "tennis neck." If notes are being taken (and they should be), it's very difficult to track the group's decisions, if any are being made.

The meeting facilitator must maintain a reasonable pace and focus, if the meeting is to be effective. Encourage participants to jot down questions and additional thoughts that are not on the topic being discussed. Then, when there is a lull in the conversation, a new topic can be introduced and everyone can track along with the new discussion.