Social copying
Social copying is adopting something because you have seen someone like you do it, which is why new things spread along an S-curve rather than a straight line.
How it works
Asking someone to be first runs against two instincts at once: they have never done it, and nobody else is doing it. So the start of any adoption curve is flat, not from indifference but from risk, and it steepens only when the next person can see the last one. Good products are killed on the flat part for failing to be an overnight success. Concentration therefore beats reach: five adopters on one street do more than fifteen spread ten miles apart, because the second sale arrives only after the first is visible.
What it changes for a personal brand
Stop trying to reach more people and start trying to be visible twice to the same small group. Five readers in one field who all know each other are worth more than fifty strangers, because the second one only arrives after seeing the first.