This concept is really important if you want to make change for a living. Take a look at the Bell Curve below.

Geoffrey Moore pioneered this idea in order to bring technology to the masses you have to jump the chasm to be relevant. The rest of us focus so much of our attention on trying to be something for everybody. But we end up being nothing to no one. And the reason is simple. You are not Walmart. You are not Amazon or Apple. You can’t hit the masses.
This is a good thing.
The internet has broken mass media. We think it is mass media but it is not. The internet is a micro-medium. Because once Seinfeld ended (they had 75 million people watching the final episode) you can’t buy that kind of attention anymore. Maybe the Superbowl but that is it. The internet broke the masses up because now you can find idiosyncratic tribes anywhere. If you want to find a group of underwater basket weavers, you can!
The internet breaks up large groups and segments them. Now, we go back to the smallest viable audience. You get to pick which audience to serve. Which to change.
How are you going to change a million people, if you can’t change one?
Start small and grow from there.