Group Brainstorming is a Bad Idea

There is a discrepancy between everyday beliefs and scientific evidence about the effectiveness of group discussion as a method of idea generation. Academics, politicians, and the business community appear to be firmly convinced
that groups can stimulate individual creativity, and procedures such as group brainstorming are still widely used in commercial organizations and advertising agencies.

Yet scientific evidence has consistently demonstrated that people produce many more ideas when they work alone rather than in groups.
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Brainstorming was developed by the advertising executive Alex F. Osborn (1953, 1957, 1963) as a technique to increase the effectiveness of group sessions at his advertising agency. He called these sessions ‘brainstorming sessions’, because ‘brainstorming means using the brain to storm a problem’ (Osborn, 1963).

Brainstorming is based on two principles which Osborn called deferment of judgement and quantity breeds quality.

The principle of deferment of judgment implies a strict separation of idea generation and idea evaluation by having different people or at least different group sessions for idea generation and evaluation. A strict application of this principle should enhance the quantity of ideas produced, and thus, according to the second principle, also the quality.

From these two principles, Osborn derived four rules for idea finding:

1. Criticism is ruled out.
2. Free-wheeling is welcomed.
3. Quantity is wanted.
4. Combination and improvements are sought.

Osborn claimed that the adherence to these rules would more than double the ideas of group members.
Empirical studies which compared the productivity of real brainstorming groups with that of ‘nominal groups’ have consistently failed to support this claim.