Positioning and segmentation · Segments and targets

Which segment first

Rank three clinic specialties by lifetime margin per acquisition dollar, pick one for the first $60,000, and find the close rate that would flip it.

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The beachhead region is chosen, and inside it three kinds of clinic compete for the first $60,000 of the year's acquisition budget. The arithmetic is the one from the beachhead lesson; the trap is a close rate measured on very few demos.

The situation

The clinic scheduler has picked its beachhead: one region of about 4,000 clinics with one to five practitioners. Three specialties make up the region, and the founder has the first $60,000 of the region's year-one acquisition budget, enough to open one of them properly. Two months of test campaigns, one specialty newsletter each, produced the demo figures below; churn is assumed from customer interviews.

Specialty	Clinics in region	Cost per booked demo	Demos	Closed	Monthly churn
Dental practices	1,600	$300	20	6	2%
Physiotherapy clinics	900	$360	11	5	1.5%
Family medicine	1,500	$250	16	4	2.5%

Every clinic pays $99 a month at 80% gross margin. Lifetime margin is monthly margin divided by monthly churn. The cost to win a clinic is the cost per demo divided by the close rate. A count of closes varies by about its square root from one batch of demos to the next.

The question

Which specialty gets the first $60,000, and how far would the number you trust least have to move to change your answer?

A strong answer · Rubric · Where answers go wrong

Write your answer first, then open

A strong answer

Monthly margin is $99 × 0.8 = $79.20 for every specialty. Rank by lifetime contribution per acquisition dollar:

            close rate     cost to win          lifetime margin          return per $
dental      6/20 = 30%     300/0.30 = $1,000    79.20/2%   = $3,960      (3,960 − 1,000)/1,000 = $2.96
physio      5/11 = 45%     360/0.45 = $800      79.20/1.5% = $5,280      (5,280 − 800)/800     = $5.60
family      4/16 = 25%     250/0.25 = $1,000    79.20/2.5% = $3,168      (3,168 − 1,000)/1,000 = $2.17

Physiotherapy, the smallest group with the dearest demo, returns nearly twice what dental does per dollar, because a physio clinic closes more often and stays longer. On payback, cumulating margin × the share still paying, physio still leads: month 11, against month 15 for dental and family. $60,000 at $800 wins 75 clinics, one physio clinic in twelve in the region, close to the one-in-ten density at which owners start hearing about the product from each other. The same money wins 60 dental clinics, one in 27.

The number to trust least is the physio close rate: 5 closes from 11 demos. Physio falls to dental's $2.96 when (5,280 − cost) ÷ cost = 2.96, so cost = 5,280 ÷ 3.96 ≈ $1,333, a close rate of 360 ÷ 1,333 ≈ 27%. Five closes vary by about √5 ≈ 2, so anything from 3 to 7 closes in 11, 27% to 64%, is plausible: the flip point sits at the bottom edge of what was measured. The churn assumption matters less: at dental's 2%, physio still returns $3.95.

So: physiotherapy, staged. Spend the first $10,000 on about 28 physio demos and commit the rest if 8 or more close, which is above 27%. Fewer than 8, and dental takes the budget.

Rubric

Computes the close rate and the cost to win a clinic for each specialty from the demo counts.
Computes lifetime margin from monthly margin and churn, and ranks by return per acquisition dollar rather than by clinic count or demo price.
Picks physiotherapy and says what $60,000 buys there: 75 clinics, about one in twelve in the region.
Finds the close rate at which the choice flips, about 27%, and notes that 11 demos cannot rule it out.
Proposes a staged spend that measures the close rate before committing the whole budget.

Where answers go wrong

"Dental: 1,600 clinics is the biggest group, and its demos are cheaper than physio's." It ranks by size and demo price, the headline mistake. What a clinic costs to win is what matters, and at a 30% close rate a dental clinic costs $1,000 against physio's $800.

"Physio: 5,280 ÷ 800 = 6.6, the best ratio, so commit all $60,000 now." The choice is right and the confidence is not. It treats 5 closes out of 11 as a measurement; a 27% close rate is inside the noise, and at 27% dental would have been the better buy.

"Family medicine: the cheapest demo at $250." The price of a demo is not the price of a clinic. At a 25% close rate a family clinic costs $1,000, and at 2.5% churn it returns the least of the three.