People don't care about your product, only the result that comes from using it.
- Identify a problem in people's lives
- Build something to fix it better than what's already out there
- Create a brand behind the product that portrays the right message
- Deliver the promised result
The following quote does a good job explaining step 3:
"People don’t buy what you do, they buy why you do it." — Simon Sinek
But don't forget, you should never start something with the sole intention of making money.