There are certain things that differentiate successful entrepreneurs from those that are just in the business for the money, and one of those things is that they learn deeply the problem they are trying to resolve. They have a lot of empathy for the users/buyers and try to bring some value to their life. 

The second characteristic about good businessmen is taking care of distribution at an early stage. It's important to find a product-market fit, but it is even better to find product-market sales fit early on. Selling the K-12 schools and districts is hard. There are entrepreneurs who are very thoughtful about their business model, pricing, revenue streams, the financing mechanisms, an appreciation for the amount of money invested already to try to address this problem, and how they might help save money and improve effectiveness - all these matters. Entrepreneurs should think about all that early in the founding of the company as opposed to figuring out product-market fit and then thinking about distribution later. So, I prefer product market sales fit as a focus from the get-go.

Looking for companies to put money into, I always ask them how much money is spent and for what, where the money comes from, who the buyers are, and how they procure them. Even if they aren’t selling a lot currently, they must understand all that deeply. In order to become an investable company, you need to build a stunning display with an understanding of the size of the market in a realistic sense of industry dynamics. This is how this actually works.