Give the ads skill a first-principles affordability gate for channel
decisions. LTV:CAC blesses channels that quietly run you out of cash: it
assumes universal churn, smooths over the front-loaded first-3-months
churn spike (Baremetrics), averages a $9 and a $999 plan into one
meaningless ratio, and ignores trial/sales-cycle revenue delay. Payback
Period (CAC/ARPU, target 3-12mo) and Discounted Payback
(CAC / (ARPU x retention)) are per-plan and time-aware, so the "can I
afford this channel?" question gets a real answer. Also captures two
adjacent stances from the source: OOH without social amplification is
wasted, and narrative-momentum ad copy tested one variable at a time.
Depth lives in references/payback-period.md (SKILL.md stays <500 lines);
wired into Reference Routing and cross-linked to attribution (CAC inputs)
and pricing (ARPU/plan structure). New eval (id 11) covers the
blended-LTV:CAC pushback + per-plan payback math.
Source: Corey Haines, Founding Marketing, ch. 7.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
