{"id":1059,"slug":"marketing-services-as-credence-good-for-gc","title":"Marketing services are a near-paradigmatic credence good for a GC buyer","kind":"reference","scope":"business","status":"current","audiences":["kevin","candid-team"],"topics":["gc-vertical","psychology-aversion","credence-goods"],"reference_body":"**Claim:** Marketing services to a GC satisfy all three Darby–Karni / Dulleck–Kerschbamer criteria for a credence good ([[darby-karni-1973-credence-goods-framework]]):\n\n1. The GC cannot evaluate the **technical quality** of the marketing work the way he can evaluate framing or rough-in plumbing.\n2. The GC cannot easily verify whether **reported outcomes** (leads, traffic, brand lift) are attributable to the agency's work or to background market factors.\n3. The GC cannot in many cases verify after the fact whether the **work itself** was actually performed at the level represented.\n\nCombined with GC risk aversion ([[kahneman-tversky-prospect-theory-loss-aversion-2to1]]), the credence-good structure produces a market in which the **default rational stance is skepticism**, not engagement. Reputational and referral mechanisms partially compensate — which is precisely why peer-referred marketing vendors close at far higher rates than cold-pitched ones, and why [[apb-sorci-2024-48-7pct-referrals-half-of-sales]] dominates lead-sourcing data.\n\n**Confidence:** Verified (application of the academic framework to the domain).\n\n**For Candid — the strategic move:** Concede the credence-good problem instead of denying it. Marketing vendors who say \"trust us, the work is real\" are arguing against information the buyer already has ([[ftc-homeadvisor-angi-jan-2023-7-2m-order]]). Candid says the opposite: *\"marketing is hard to inspect; here is exactly how we make it inspectable.\"* Published process, published reporting, named-deliverable contracts, refusal-to-quote-cold — all forms of conceding the problem rather than pretending it doesn't exist. Operationalized as [[rule-concede-credence-good-problem-make-marketing-inspectable]].","rationale_body":null,"metadata":null,"links":{"outgoing":[{"slug":"research-brief-psychology-gc-marketing-aversion-may-2026","title":"Research brief: the psychology of marketing aversion among general contractor owners (May 2026 foundation)","kind":"reference","scope":"business","link_type":"relates-to"},{"slug":"darby-karni-1973-credence-goods-framework","title":"Darby & Karni (J Law Econ 1973) — \"credence good\": quality consumers never discover even after consumption","kind":"reference","scope":"business","link_type":"depends-on"}],"incoming":[{"slug":"rule-concede-credence-good-problem-make-marketing-inspectable","title":"Rule: concede the credence-good problem; make marketing as inspectable as possible","kind":"rule","scope":"business","link_type":"depends-on"},{"slug":"rule-hba-chba-peer-channels-as-primary-distribution","title":"Rule: treat HBA / CHBA / RenoMark / peer channels as primary distribution, not soft-marketing tactics","kind":"rule","scope":"business","link_type":"depends-on"},{"slug":"design-build-leading-edge-million-dollar-buyer-pays-for-design","title":"Design-build / custom-residential leading edge — $1M+ buyer pays for design, which is itself a credence good","kind":"reference","scope":"business","link_type":"depends-on"}]},"created_at":"2026-05-24T23:24:06.308Z","updated_at":"2026-05-24T23:24:06.308Z"}