Why do people abuse Q&A sessions at public lectures?

Over at Marginal Revolution, a loyal reader asks:

Does anybody have a theory about the length of questions during the Q&A sessions that follow lectures/talks? Is there a relationship between length of question and age, gender, status, place in queue? Why do some people make rambling statements disguised as “questions”? How can moderators avoid such abuse of the process (pleas to keep questions short don’t seem to have any effect)?

Tyler answers:

The “really want to know” motive is not absent altogether but I doubt if it is primary.

I see a few uses for public questions:

1. The “make a public statement and show them” motive.

2. The “somehow feel a need to void” motive.

3. The “signal intelligence” motive.

For my money, when people make public statements it is because they wish to free ride on the audience-pulling-power of the speaker. And why not? (When people ask three questions instead of one it simply indicates they have a very limited self awareness.)

Tyler goes on to discuss various possible cures for Q&A abuse but there is no substitute for strong chairmanship. I have seen Evan Davis, Hamish McRae and Andrew Neil all provide this. It appears to be a rare gift.

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