Verified against Claude · 2026-08-06
Audit your product-market-fit signals honestly instead of eyeballing 'traction'
Turn survey, retention, and channel-mix data into a structured PMF signal audit using the Sean Ellis "very disappointed" threshold and retention-curve shape — a real read, not a vibe.
The prompt
Ready to copy — highlighted parts are example details you can swap.
You are auditing product-market-fit signals honestly — the goal is an accurate read, not a comforting one. Context: - Company stage: Seed stage, 8 months post-launch - Sean Ellis "how would you feel if you could no longer use this product" survey results, if collected: 80 responses: 22% very disappointed, 51% somewhat disappointed, 27% not disappointed - Retention/cohort data: Week 1: 100%, Week 2: 48%, Week 4: 31%, Week 8: 29%, Week 12: 28% - Growth channel mix (organic/referral vs. paid), if known: Month 1: 90% paid ads / 10% organic. Month 4: 60% paid / 40% organic, paid spend flat Task: 1. If 80 responses: 22% very disappointed, 51% somewhat disappointed, 27% not disappointed is given, restate the percentage who said "very disappointed" without the product, and state plainly whether it clears the commonly cited ~40% threshold. Label this as a widely-used rule of thumb, not a guarantee of anything, and note explicitly if the sample is too small to trust the percentage at all. 2. Read Week 1: 100%, Week 2: 48%, Week 4: 31%, Week 8: 29%, Week 12: 28% for curve shape: does retention flatten after the initial drop-off (a "smile curve," the real PMF signal), or does it keep declining toward zero with no flattening (a "death spiral")? State which, and point to the specific numbers in the data that support your read. 3. If Month 1: 90% paid ads / 10% organic. Month 4: 60% paid / 40% organic, paid spend flat is given, treat a rising organic/referral share against flat or falling paid spend as a secondary PMF signal, and paid-dependent growth with no organic pull as an absence of that signal — state which applies. 4. Give one honest overall verdict — Strong signal / Mixed or early signal / No signal yet — and explicitly refuse to round a mixed result up to "we have PMF" just because some inputs looked good. Format: four headed sections ending in one blunt verdict line.
Customize the highlighted detailsoptional — the prompt above already works
Why this works
This uses two specific, evidence-based PMF heuristics instead of a vibe check: the Sean Ellis survey's ~40% 'very disappointed' threshold — the benchmark Superhuman famously used to drive its own product roadmap toward PMF — and the retention-curve 'smile vs. death spiral' shape, the standard way growth teams distinguish real product-market fit (usage stabilizing among a core group) from a leaky bucket that only looks like growth because acquisition spend keeps refilling it. The instruction to refuse rounding mixed signals up to 'we have PMF' directly targets founder motivated reasoning — self-assessed PMF calls are one of the most consistently over-optimistic judgments founders make about their own company, precisely because a 22% very-disappointed score and a retention curve that hasn't flattened yet are each individually easy to explain away, and much harder to explain away side by side.
What you get back
Survey: 22% very disappointed — below the ~40% rule-of-thumb threshold, though 80 responses is a reasonable sample size to trust this read at seed stage. Retention: Curve flattens from week 4 (31%) through week 12 (28%) — this reads as an early smile curve, not a death spiral, since it's stabilizing rather than continuing to decline. Channel mix: Organic share rising (10% → 40%) while paid spend holds flat — a genuine secondary PMF signal, since it isn't just more ad spend producing more signups. Verdict: Mixed / early signal. Retention and channel mix both point toward real pull, but the survey score alone doesn't clear the PMF threshold — treat this as promising, not confirmed.
Verified against
Claude Sonnet 5 · 2026-08-06
ChatGPT GPT-5.1 · 2026-08-02
Changelog
- 2026-08-06 — Initial publish.
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