Groups chats work as social networks because of social pressure tricks:
• Read receipts
• Displaying "John was online 43m ago"
• Continuous pressure to reply "enough"
• Small chats can have strong norms (no outrage/politics) implicitly enforced per reply
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Small group chats (≤5 people) create a constant "are you in or out?" pressure. Everyone knows who responds and shares the least. If you're in a 4 person chat w/ daily enthusiastic activity from the others, they might move to a 3 person chat w/o you if you don't engage for weeks
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Small group chats (≤5 people) are good at enforcing strong norms like no politics/outrage. Chats implicitly enforce per-member participation. If one member gets political regularly and others don't like it, they'll prob move to a chat w/o them. This usually isn’t explicit too!
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