Critical Mass
The minimum amount of something required for a process to become self-sustaining. Below this threshold, the system cannot sustain itself; above it, the process accelerates under its own momentum.
Biological Context
In bacterial colonies, quorum sensing triggers collective behavior only when cell density reaches a threshold. Predator populations need minimum numbers to sustain viable breeding. Forest fires require minimum fuel density to spread. The threshold separates qualitatively different outcomes—below it, things fizzle; above it, they take off.
Business Application
Network products, marketplaces, and platforms all have critical mass thresholds. Below minimum users, a social network has no value. Below minimum liquidity, a marketplace fails to match buyers and sellers. Understanding where your critical mass threshold lies—and designing launch strategies to cross it quickly—separates successful platforms from expensive failures.