Love the problem if you don't know what it is
Although I agree with the core view behind, this approach fails short for people who are coming from a science/academic background.
First, you must love the solution.
Probably you spent years building something and if you are not in love with it, there is no way to keep pulling through, either as an entrepreneur or as a scientist who keep building on it.
It is extremely hard to know what problem you are going to solve when you are spinning our from the university. Probably, what you thought were problems are self-fabrications. It's extremely hard to know what the reality in an industrial setting is, or what someone from a different field does on a daily basis.
At some point, it must be acknowledged that at the beginning, the first job of scipreneurs is to explore the parameter space of their solution. Find as many use cases as possible, and narrow down on the ones that resonate the most.
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