Bmc Channel Economics Check

BMC Channel Economics Check

Purpose

Channels are usually listed on a BMC the way they'd be listed in a marketing plan — "outbound sales, content marketing, referrals" — with no cost attached to any of them. This skill forces a number onto every channel before it's accepted onto the canvas: what does it actually cost to acquire a customer through this channel, and can the business afford that cost at the volume it needs? Use once Channels has a first draft and bmc-economic-prototyping has established a price and margin to check the cost against.

Anchored in research

Standard SaaS/growth-marketing unit-economics discipline — customer acquisition cost (CAC), lifetime value (LTV), and CAC payback period are widely practiced, general-purpose metrics, not tied to a single named source. Commonly cited practitioner ranges (e.g., an early-stage company generally wanting CAC payback under roughly 12-18 months) are treated here as an order-of-magnitude guide, not a verified universal benchmark — the real threshold in Step 4 below always comes from the specific company's own budget and runway, not a rule of thumb.

Method

1. List every channel on the canvas separately — outbound sales, inbound/content, paid acquisition, partnerships/referral, marketplace/platform, direct. Don't group them; each has its own economics.
2. For each channel, estimate the CAC components honestly:
   • Direct cost per lead or impression (ad spend, event cost, tooling).
   • Conversion rate from lead to paying customer, at each stage if the funnel has more than one.
   • Time cost — sales cycle length, and the fully-loaded cost of the people involved (a channel that "costs nothing" in ad spend but eats three weeks of a founder's time is not free).
   • Any channel-specific tooling or platform fees.
3. Compute a blended CAC per channel and compare it to two things at once: the price/margin bmc-economic-prototyping already established, and the actual budget realistically available for that channel (not an aspirational number).
4. Run the payback period check. CAC ÷ (revenue per customer per period × margin) = months to payback. Compare this against the company's own cash runway and patience threshold — a company with 8 months of runway cannot tolerate a 24-month CAC payback the way a well-funded one can, regardless of what "normal" looks like in a generic benchmark. The threshold is set by THIS company's actual cash position, not a rule of thumb from a different kind of company.
5. Check volume feasibility, not just unit cost. A channel can have attractive per-unit CAC and still fail if it can't produce the volume needed to hit the revenue target established in bmc-economic-prototyping's "big enough" question — a channel that's cheap per customer but can only ever deliver ten customers a year is not a scalable channel, it's a nice-to-have.
6. Watch for channel novelty bias. A common trap: a channel gets added to the canvas because it's currently fashionable ("we should do TikTok," "let's try a Product Hunt launch") without anyone costing it first. Every channel on the canvas should have survived steps 2-5 before it's treated as part of the plan, not just brainstormed onto a sticky note.
7. Decision rule. If CAC payback exceeds the company's own runway-adjusted threshold, OR the channel can't sustain the volume needed at any affordable spend level, either redesign the channel (different targeting, different offer, different price point feeding back into bmc-economic-prototyping) or drop it — don't keep an unaffordable channel on the canvas "for completeness."

What this skill does NOT do

• Doesn't build a full customer lifetime value model — for a rigorous LTV calculation feeding a business case, hand off to business-case-and-analysis/roi-npv-sensitivity-model.
• Doesn't design the channel's actual marketing execution (ad creative, content calendar, sales scripts) — it only tests whether the channel's economics justify pursuing it at all.
• Doesn't apply a fixed, universal CAC payback benchmark as a pass/fail gate — the real threshold always comes from the specific company's cash runway, not a generic number.

Refinement notes

• What's your own real CAC payback threshold when advising early-stage clients — how much does it actually flex by runway and stage in practice?
• Which channel do clients most often overestimate the economics of before this check, and which do they underestimate?
• Have you seen "channel novelty bias" (Step 6) derail a client's channel strategy? What did the correction look like?

Continue from here

• Uses: bmc-economic-prototyping/SKILL.md — the price/margin and revenue target this skill checks channels against.
• Feeds into: business-case-and-analysis/roi-npv-sensitivity-model for a full LTV/CAC model once the channel mix is set.
• This pack's shared guardrails: ../../CLAUDE.md

References

• ../../references/bmc-source-material-notes.md — source material background
• ../../references/bmc-resilience-heuristics-research.md — selection and grounding notes for this skill and its siblings
• ../../CLAUDE.md — this pack's shared guardrails