Show that you test assumptions before building. Describe the cheapest way you validated demand: a landing page, a Wizard of Oz prototype, or concierge testing.
Strong answers show a structured discovery process: problem framing, customer interviews, competitive analysis, prototyping, and risk assessment (value, usability, feasibility, viability). Best candidates mention dual-track development and specific techniques like opportunity solution trees or assumption mapping.
Tests product thinking depth. Weak candidates skip straight to building. Strong candidates have a systematic way to reduce risk before committing resources. Ask: "What do you do when discovery results are ambiguous?"