Cliff Kuang, writing for Fast Company Design:
The business practice of brainstorming has been around with us so long that it seems like unadorned common sense: If you want a rash of new ideas, you get a group of people in a room, have them shout things out, and make sure not to criticize, because that sort of self-censoring is sure to kill the flow of new thoughts.
In the opening paragraph, Kuang builds a straw-man version of brainstorming as "everyone shouting ideas". Unfortunately, this is what everyone thinks of when they think brainstorming.
Putting people into big groups doesn’t actually increase the flow of ideas. Group dynamics themselves--rather than overt criticism--work to stifle each person’s potential.
The point of brainstorming as a process is not to silence criticism but to impose good group dynamics so everyone's ideas get at least heard.
But Lehrer goes on to point out that other studies have shown that the presence of criticism actually increases the flow of ideas.
Yes. The brainstorming process is about giving ideas and their criticism a voice. It was primarily developed to help dysfunctional companies work well. What would happen in these companies is someone would say an idea, someone else would criticize it, and then the group would break into two camps: those saying "stop being so critical!" and those who just wanted the meeting to be over. The meeting would turn into a fight and nothing would get done.
Brainstorming was developed to structure the meeting so that this fighting wouldn't happen. You divide the time into idea generation and idea development. In idea generation, there is no criticism. This lets everyone in the "stop being critical" camp feel listened to. Then you start talking about the ideas, which lets the actual work get done. And it turns out that sometimes what turned out to be the best ideas would have started a fight in the old meetings. With brainstorming, everyone feels productive and happy.
But if your group dynamics are working well, you probably don't need that kind of structure.
It might surprise some businesspeople that brainstorming has books written about it, and that you can read those books, and then learn something. Going deeper is often just as edgy and controversial as criticizing a popular but inaccurate idea. It might also surprise businessfolk that brainstorming is just the beginning. There are many systems for helping meetings work better. I recommend De Bono's Thinking Course and How to Make Meetings Work!.