My understanding of Flexport’s journey is the same as this. Ryan had insight into the fact that shipping stuff across the globe is difficult from his previous businesses. He created a landing page offering to import shipments into the U.S., first shipment free, and had a couple major signups. He had someone build him a prototype and he continued to validate his idea while he waited for an import license. Flexport did all 4 MVP steps listed above, but they also identified and established a moat early on.