"This bug tracker is crap. I could do a better job. "
You ask your friend. They agree.
So you draw out a rough spec and you start coding.
It’s the best code you’ve ever written.
You work long into the night.
You even add some documentation - not that anyone will need it because it’s so intuitive.
You write the introductory blog post.
You out a video on YouTube. You blast it out on all your socials.
And get nothing.
Because you made the first mistake of launching a product.
You started with an idea. And ideas don't sell.
You need to start from research.
"Who is this for? What problems do they have? What will they pay for? How do they describe it? Why should they trust me?"
Start by discovering the answers to those questions. And in doing so, you'll build an audience for your product before you even begin.
And that means that your product fills a need that people will pay for and you'll be able to launch to actual sales.