You're Not Building One Product — You're Building Two. Here's What That Means for Your Marketplace.

Marketplace consultant Darren Cody opens with a deceptively simple provocation: a marketplace is not a product. His argument is that a marketplace is actually two products — one for buyers, one for sellers — stitched together by a transaction. Every assumption you carry in from traditional product thinking, where you build for one user type with one core job to be done, will quietly undermine you when applied to a marketplace context. This is the foundational reason marketplace specialists exist as a distinct discipline.

Most 0-to-1 marketplace founders come from one of two backgrounds — they either think like a SaaS builder focused on a single user journey, or they think like an e-commerce operator focused on conversion. Neither mental model accounts for the simultaneous, interdependent needs of two completely different user groups who only generate value for each other. If your supply side is unhappy, your demand side has nothing to buy. If your demand side is thin, your supply side churns. The chicken-and-egg problem isn't a launch quirk — it's a permanent structural tension baked into the marketplace model itself.

The deepest insight here is that marketplace failure is usually a coordination failure disguised as a product failure. Founders who treat the marketplace as a single product tend to over-invest in one side — typically the buyer experience, because that's where revenue signals are loudest — while neglecting the operational, motivational, and trust needs of the supply side. The transaction that connects both sides is not a feature; it is the product. That means your north star metric should measure the health of the match between supply and demand — not just traffic, signups, or GMV in isolation. A marketplace consultant's real job is to stress-test whether the conditions for a reliable, repeatable transaction exist on both sides simultaneously, before you've spent your runway finding out the hard way.

• Write two separate one-page product briefs — one for your supply side, one for your demand side — and check whether each stands on its own as a compelling value proposition before the other side exists.

• Map your transaction: identify every step between a supplier listing and a buyer completing a purchase, then mark which steps create friction for each side independently.

• Audit your metrics dashboard — if every metric you track is demand-side (traffic, conversions, revenue), add at least two supply-side health metrics such as listing quality score or supplier repeat activity rate.

• Before engaging any technical resource, ask a marketplace-experienced advisor to challenge your liquidity assumption: in your target market, is there enough supply density in a small enough geographic or category niche to generate reliable matches from day one?

• If you're considering a marketplace consultant, test their thinking by asking them to describe the failure mode they see most often on your specific supply side — a generalist will give you a generic answer; a specialist will name something uncomfortably specific to your model.