This is something that I wished I had understood way earlier in my career. Basically that cause and effect are often inverted when people talk about the network effect. People who do some thing well, or are passionate about, often will accumulate a network of others who are interested in that same thing. And because they know a bunch of people who are also interested in that thing, when they hit a roadblock or a problem they have people they can reach out to for help or insights.
What is hard is discovery which is to say that the greatest programmer in the world who sits in his shack and writes perfect code that is beautiful and functional, is invisible.
There is a joke about the guy who complains "I make no money at all from stocks." and the friend says "What stocks do you own?" and the complainer responds "Oh I don't own any stocks, have no use for them, I just want money from them."
Attention and focus is like 'money from stocks' if you share what you're doing and your understanding with people you give them some advantage and perhaps some new understanding. That advantage comes back in the form of referrals or opportunities that you were not present to see when the person you shared with recognizes an opportunity as something you would be interested in. It also allows you to be "discovered" two or three hops down the road when someone says "Oh I know someone who is interested in that ..."