Psychologists usually offer three explanations for the failure of group brainstorming. The first is social loafing: in a group, some individuals tend to sit back and let others do the work. The second is production blocking: only one person can talk or produce an idea at once, while the other group members are forced to sit passively. And the third is evaluation apprehension, meaning the fear of looking stupid in front of one's peers.

Auteur: Susan Cain