Everett Rogers grew up in farm country. In Iowa. He was fascinated by why farmers were so slow to innovate, to take on new ideas that would save them both time and money.
His studies, summarised in his book The Diffusion of Innovation, revealed that the block was not so much the product as the waiting to see what other people do.
He found a small group of innovators ready to try any new idea, ready to be ahead of the crowd. Behind them came the early adopters, a larger group, ready to take a risk but only after the innovators have shown that the innovation isn’t a dud. After them come the early majority, the late majority, and the laggards, the most reluctant adopters of all.

No self-respecting business gets off the ground without reference to Rogers’ work. It has been core to our efforts to help social innovators scale.
For example, we worked with Safe Families for Children, an organisation that finds volunteers to support children who would otherwise come into care. We got out the back of an envelope. We wrote down 150, the number of local authorities in England. We multiplied that by 2.5% and decided to test the concept out with a handful of early adopters. That seems to work, so we got out the calculator and envelope again and decided we needed 20 early adopter local authorities. That seemed to work also, so then we went home.
Today Safe Families is well into the early majority local authorities. They do it not because Safe Families is effective but because other local authorities use the innovation. ‘Have you heard about what they are doing in (the neighbouring authority)? We should do it to’.
Which is the point of including the example. It is another illustration of positive contagion.
Here is a nice, short TED talk that represents the same idea with a little humour.