Individual vs in crowd
Individuals who find themselves members of a large coherent group or crowd, especially one that is emotionally excited, may become swept along to support the group’s decision, even though the same individuals might have rejected the decision if allowed to reflect on it alone at leisure.
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Bad vs good approach
As Irving Janis pointed out in his book Groupthink, the Bay of Pigs deliberations exhibited numerous characteristics that tend to lead to bad decisions, such as a premature sense of ostensible unanimity, suppression of personal doubts and of expression of contrary views, and the group leader (Kennedy) guiding the discussion in such a way as to minimize disagreement. The subsequent Cuban Missile Crisis deliberations, again involving Kennedy and many of the same advisors, avoided those characteristics and instead proceeded along lines associated with productive decision-making, such as Kennedy ordering participants to think skeptically, allowing discussion to be freewheeling, having subgroups meet separately, and occasionally leaving the room to avoid his overly influencing the discussion himself.
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