The phenomenon of 'Groupthink' leads to ego clashes and reinforcement of existing biases. They somethings fail to reach any decision and may complicate matters further by incorporating all points of view. Design by Committee is something best avoided.
Brainstorming, on the other hand, involves creative, divergent thinking, which is different from the restrained, critical thinking that may be required to come to a decision.

Groupthink

People with better social sensitivity and an emotional perception(higher EQ) are a better hire than those with individual performance scores. 
Humble people who listen attentively, and admit their mistakes become enablers in the team leading the group achieving it's fullest potential. The team as a whole begins to behave in the same way and increase its overall collective intelligence.

Humble Leaders

An extensive study in 'Groupthink' which included testing the social sensitivity, as well as the IQ of the individuals, showed that:
<ul>
<li>Equal participation was a key ingredient of better performance. Group dynamics can get worse if team members clash frequently.</li>
<li>If team members are pitted against each other for a common prize, like a promotion, then group work suffers.</li>
<li>If team members are not open to ideas from other members or are interrupting them, it can sabotage group performance.</li>
<li>Teams with a higher proportion of women have better collective intelligence.</li>
</ul>

Collective Intelligence

Collective intelligence or group thinking is an idea that by many minds working together, we can correct each other's errors in judgment and provide good results.Companies employ intelligent, well-qualified people and assume that this will automatically accelerate magical outcomes. But collective reasoning, while being useful, also has inherent pitfalls.

Wisdom Of The Crowd

High-flying individuals, whose self-beliefs often impair their abilities o cooperate with others, can lead to a downfall of the team.
The constant jockeying for authority and imposing one's viewpoint/decisions hamper the team's performance.
Too much talent inside a team can be counterproductive, according to a study on the 'star players' in the financial sector.

The Pecking Order

This is an edited extract from The Intelligence Trap: Why Smart People Make Dumb Mistakes. Iceland should never have made it to the Euro 2016 men's football tournament. Four years previously, they were ranked 131st in the world.

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