A business for the sake of just making a business feels wrong. A business for the sake of making an awesome product feels right.
You're free to start a business by building the product of your dreams, but no matter how much you personally like it, there's no guarantee people will pay for it. In other words, if you want money, but start with building a product, you're likely to have a bad time.
But if you just want to build an awesome product, and don't care about whether you make any money with it, then there's no problem.
I'd suggest instead that identifying an audience for a potential product is actually part of making an awesome product.
There's a pretty wide stretch of territory between not caring whether something is business viable and only caring about building a successful business.