Shooting an arrow at a wall and then painting a target around it
There is absolutely no surefire way to guarantee that your side-project will ever be anything more than a hobby that pays for itself. But there are some surefire ways to guarantee that you'll get to failure sooner rather than later.
1. Building something in the latest and greatest tech and then trying to find a problem it solves.
Don't do this. I see it too often, especially on Indie Hackers. This is a Rube Goldberg way of trying to accomplish your end goal and will lead most likely to frustration and burnout.
2. Your idea doesn't solve a problem.
Pivot. Come up with an idea that solves a problem. Preferably a problem you have.
3. You're not passionate about what you're doing.
Be honest with yourself. Really honest. Can you imagine working on this the next 5-10 years? If not, don't waste time on it now. Spare yourself the misery.
4. We're going to be first-to-market!
Unless you want to scoop up some early adopters, being first to market only indicates that there might not actually be a market for what you're doing.
5. If I build it, they will come.
No they won't. They really won't. This ties back to #1.
6. I want to be my own boss.
Running a startup is the most brutally demanding work you will ever do. It is 10x easier to be a drone for a corporation; maybe 100x easier if it's a regional co.
7. I'm afraid to ________
You cannot be scared. Not of rejection, failure, embarrassment, ridicule by your peers, ridicule from the world, etc. Being a leader isn't easy and your mettle needs to be unbreakable, unflinching, and unquestionable. --
That's all of the harsh truth that I can muster for now. Even though I don't know you, I want you to succeed.