Bottom-Up
Early in my career, as an engineer at Gambro (a Swedish medtech company), I was taught a simple method for expressing the core of the benefits of an offering to a client. The method requires the use of only a verb and a noun to explain what the customer needs.
For example, if you manufacture pencils, the “verb + noun” description is “make mark,” or if you manufacture jewelry and tie clips, the expression is “hold tie.” It is obvious that the business, market, and competitors will be completely different if you provide a solution to “make a mark” or “hold a tie” versus offering a pencil or a tie clip.