When you finally connect what you love to do to what a lot of people love to buy. When you can focus all you want and still have unlimited work and fun.
When the high voltage line (dream, ambition, hope) is connected to ground reality (business, pay, likes, followers).
Having found what people want, not just what people may need. Your offering and their acceptance is sure, no longer a guess. You can provide it for profit, and you can indeed making living on it. Traction is sometimes called validation. You are no longer a theater. You have touched nature, and found cash vein.
My intended customers are searching for something I offer, instead me reaching out and peddling all the time. It means you have found that you offer something people WANT (not people need) and that they are willing to pay you in a way that you can pocket some profit. You have found the connection is valid.
I can see my customers directly through the channel and market and funnel now. I know what they want, I know what they search for. I know what problem is number one on their mind. And I know I provide exactly what the audience is searching for with a great value, and I can make a profit. When traction is there, the sense is mushroom growing, not pig flying.