We tend to think that groups are better than individuals at making big, critical decisions because groups better represent everyone's perspective and feel more 'fair' than individual decisions. There is a common wisdom is 'two heads are better than one.'
While groups can regularly out-perform the average individual at decision making, they still typically make worse decisions than the best individual (i.e., the most expert) in the group would make on his/her own. Only groups with exceptional processes out-perform the average and best individual members2,5,15.
When your brain is in the midst of making a decision, it rapidly switches between alternatives (not unlike how different alternatives keep bubbling in and out in group conversation). When a choice has been arrived at, the neural networks associated with the chosen option get louder, and the neurons associated with the failed alternatives grow quieter.
Similarly, science views groups as a holistic, information processing systems, where alternatives are tested and discussed, and decisions are swayed by emotions and loud voices until consensus is reached and the group settles their discussion with some action3,14,15.
Groups typically strive to achieve consensus, and tacitly pursue that common ground, but this creates its own bias. By seeking common ground, groups focus on information and opinions that individuals already share, which fails to incorporate uniquely valuable information that one individual may have.
For their part, individuals in the group ultimately push consensus toward the option that vibes well with them emotionally and also seems to be 'sticky', meaning that the group 'keeps coming back to that idea'2,13,14.
When people enter a group setting, they are constantly aware of others. They factor in who's powerful, who's high status, who's respected by the team, and who's intimidating or dominant. And they can change their preferred decision just by passively observing other people's interactions in the group, and what is being rewarded and punished4,9.
People walk into a group meeting with their own preferences and biases, which they often spend the whole meeting subtly confirming (by paying attention to confirmatory points and filtering-out contradictory information). Further, group settings can polarize ideas and opinions, amplifying majority opinions and suppressing minority preferences. And the larger the group size, the more it exaggerates biases7,15.
'Groupthink' occurs when group members are so enamored with their own 'groupiness' and perceived competence that they commit critical decision-making errors. Cohesive groups who feel a strong bond with each other are also potentially the highest-performing groups, but may also be the most vulnerable to groupthink. Symptoms of groupthink include:
Research on decision quality has shown that a group's process is the most important factor in its decision quality. An effective group is one that operates on a process that efficiently processes and shares information, picks up on subtleties that individuals alone might miss, and overcomes personal biases1,12.
Each group member knows nuggets of uniquely valuable information to relevant to the decision. Groups overwhelmingly fail to discover this unique information, and instead fixate on discussing common/shared information and opinions, perhaps because of the drive towards consensus, or because it's socially rewarding to feel 'on the same page' with others and socially isolating to have a different opinion. The undiscovered unique information is called the 'hidden profile.'
Groups that strive to draw out and pool together each person's unique 'data points' relevant to the problem — getting the fullest possible information on the table before making a decision — are, on average, eight times more likely to find a solution to a given objective problem[8,](https://doi.org/10.1177/1088868311417243 https://doi.org/10.1177/1088868311417243 "Lu, L., Yuan, Y. C., & McLeod, P. L. (2012). Twenty-five years of hidden profiles in group decision making: A meta-analysis. Personality and Social Psychology Review, 16(1), 54–75. ")13.
At work, most group decision making happens in meetings. Research on group decision making recommends that — rather than including everybody in a meeting or only relevant people — you add-in relevant people in stages. This is called the stepladder technique, which has been shown to improve the decision quality in meetings.
Most stepladder meetings lead to better decisions than both typical meetings and even than the best team member can make on his/her own. And the stepladder technique can boost the effectiveness of phone meetings too.
The stepladder technique: