Project Communication Channels Formula: n(n-1)/2 Explained

Quick answer

n(n-1)/2: the number of communication channels — 5 people = 10 channels, 10 = 45 — the math of why big teams communicate poorly and why meetings scale badly.

The formula

n(n-1)/2 — each person talks to every other; the count grows quadratically.

The implications

5→10, 10→45, 20→190 — coordination cost grows faster than team size.

In practice

Structure beats count — channels through hubs (PM, leads) instead of all-pairs; the formula explains why.

The PMP favorite

The exam loves it; the lesson is real — keep teams small, communicate through structure.

Bottom line

n(n-1)/2: the number of communication channels — 5 people = 10 channels, 10 = 45 — the math of why big teams communicate poorly and why meetings scale badly.

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