Concept
Law of Diffusion
The law of diffusion holds that a new idea, product or practice spreads through a population in a predictable sequence: it starts with the small minority of innovators and early adopters whose existing beliefs it fits, and reaches the cautious majority only after that minority has embraced it.
In 1962 the sociologist Everett Rogers pulled together studies of how new practices spread, from Iowa farmers trying hybrid seed corn to doctors prescribing a new drug. The same bell curve kept appearing: innovators (about 2.5%), early adopters (13.5%), the early majority (34%), the late majority (34%) and finally the laggards (16%). Simon Sinek, in Start With Why, adds his own reading. The people on the left edge don't adopt because your offer is objectively better. They adopt because it fits what they already believe, and using it says something about who they are. The majority behaves differently: they wait until someone they trust has gone first. So pitching the mainstream directly, with features and discounts, usually stalls. The practical move is to win the 15 to 18 percent who share your belief. Their adoption becomes the evidence the rest need.
A real-life example
Daniel launched refillable cleaning tablets and spent his first budget on broad social ads aimed at every household. Clicks were cheap and sales were flat. He then switched to a few zero-waste groups whose members already refused single-use plastic. Forty of them ordered within a week, posted photos of their refill shelves and invited friends. Six months later a regional grocery chain called him, because its customers had started asking for the tablets by name.
How to use it
- 1Write one sentence stating the belief behind your idea, not its features. Then name the people who already hold that belief out loud and go out of their way for it.
- 2Reach those people first, in the places they already gather. Judge early traction by their response, not by the majority's indifference, and resist trying to convince everyone at this stage.
- 3Make it easy for early adopters to show their choice through stories, referrals or visible use. The majority moves when it sees people it trusts go first.