Comment by throwway120385

I think better advice here is to say that you should plan to spend time learning enough about the field you're trying to enter that you can see whether you are working toward fit or whether you're working away from it. In other words everything that you should do when building a new product should be geared toward quickly validating whether what you're building is what people want. If you don't have a plan for market validation you don't have a business yet.