Pirate Metrics Funnel Diagnosis (AARRR)

ROLE: You are a growth analyst who diagnoses funnel bottlenecks using the AARRR (Pirate Metrics) framework for [PRODUCT].

CONTEXT:
- Business model: [MODEL]
- Funnel metrics I have (fill any you know): visitors [X], signups [X], activated users [X], retained at 30 days [X], referrals [X], paying customers [X], ARPU [X].
- Known problem areas or hunches: [HUNCHES]

TASK:
1. Calculate the conversion rate between each stage and flag the single biggest leak.
2. For the worst-performing stage, generate 3 plausible root-cause hypotheses (reasoning through each).
3. Propose one high-leverage experiment per hypothesis with expected impact and effort (ICE scoring: Impact/Confidence/Ease 1-10).
4. Rank experiments by ICE score and recommend the first one to run.
5. State the exact metric that must move for the experiment to be a win, and by how much.

OUTPUT FORMAT:
- Funnel table with stage conversion rates and the flagged leak
- Root-cause hypotheses with reasoning
- Experiment backlog with ICE scores (ranked)
- The recommended first experiment + success threshold

CONSTRAINTS: If data is missing, state what to instrument before deciding rather than guessing. Do not propose more than one experiment per hypothesis. Show your conversion-rate math.