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Viability — desirable and broke is still broke

The dimension that quietly kills real, customer-having businesses. Does the math close to your goal? Answer it in thirty seconds, on paper.

In LEANSpark

Your job: find out in thirty seconds whether the math can even close to your goal.

Run the viability check
Run this in LEANSpark
Via MCP
Read `business_model://current` and `offer://current`. Set the MSC goal, compute customers-needed = goal ÷ annual-revenue-per-customer, round price to a power of ten to find the go-to-market animal, and judge whether each segment's market is big enough to supply that many.

claude mcp add --transport http leanspark https://leanspark.ai/mcp Connect first →

What you get back

Runs the Rapid Viability Test — MSC goal ÷ revenue-per-customer = customers needed — rounds your price to a power of ten to find your go-to-market animal, and asks whether each segment's market can supply that many. A Fermi estimate, not a spreadsheet.

Your animal, the customers-needed number, and a viable / too-small read per segment against your goal.

This is the big one — the dimension that killed CloudFire, and the one I’d run first if I could run only one. Viability asks the question desirability can’t: does the math close to the goal? You can be desirable and still broke — twelve in, four out.

You answer it with a back-of-the-envelope Fermi estimate — the Rapid Viability Test, in three steps.

Step one — goal sizing. Your Minimum Success Criteria (MSC): the annual recurring revenue that makes this worth your three years. Think in powers of ten. Level one, $100K — enough to quit your day job. Level two, $1M — a small company. Level three, $10M — a VC-backable business. Level four, $100M — a unicorn. Steve is after Level three: $10M.

Step two — customer sizing. Your average revenue per customer per year, rounded to the nearest power of ten. This picks your animal, and your animal picks your whole go-to-market:

  • $10 flies — you need a million customers; you’d better be viral.
  • $100 mice — a hundred thousand; product-led.
  • $1,000 rabbits — ten thousand; inside sales.
  • $10,000 deer — a thousand; field sales.
  • $100,000 elephants — a hundred; enterprise.
  • $1M whales — ten named accounts and multi-year sales cycles.

Steve, at $500/month (~$6K/year), is a deer.

Step three — market sizing. Customers needed = goal ÷ revenue-per-customer. Steve: $10M ÷ ~$10K ≈ 1,000 customers by year three. Now the real question isn’t “is that a lot” — it’s is the market big enough to supply a thousand of them, and can you reach them at that price? If the number lands somewhere your market can’t fill, that’s a “no” you just got for free, in thirty seconds.

Desirable ≠ big enough. Viability is the most common place a real, working, customer-having business quietly fails. A segment can want your product badly and still be too small — or too expensive to reach — to ever reach the goal. This is where “worth pursuing” grows teeth: it’s where desirable meets big enough.