Human craves the sense of belonging. We formed tribes to communicate “we are of the same kind; others are not.”
We joined cliques at work, privileged memberships, exclusive clubs, and social media groups.
When the group we formed gets too big, the increased communication channels become challenging and the sense of belonging reduces. Inevitably, smaller subgroups sprout out.
Subconsciously, joining a group makes us more likely to defend the in-groups and undermine the out-groups.