Module 1: Lead Generation Economics & Commercial Targets
Lesson 6 · Lead Generation Economics & Commercial Targets
Lesson 6 objective
Build an integrated economics model connecting media cost, raw leads, qualification, sales conversion, CAC and customer contribution.
By this point, you have several useful metrics:
CPL, qualification rate, cost per qualified lead, opportunity rate, close rate, CAC and customer contribution.
The next step is to stop viewing them independently.
Your lead generation economics are a system. A change in one stage alters the value of every stage before it.
Spend
Clicks
Leads
Qualified
Customers
Contribution
1. Start with the entire economic chain
Imagine the following Google Ads programme:
| Input | Value |
|---|---|
| Media spend | £10,000 |
| Raw leads | 125 |
| Raw CPL | £80 |
| Qualification rate | 40% |
| Qualified leads | 50 |
| Qualified lead → customer rate | 20% |
| Customers | 10 |
| CAC | £1,000 |
If each customer generates £1,600 contribution before media:
10 × £1,600 = £16,000 total contribution before media.
After £10,000 of advertising:
Contribution after media = £6,000.
2. The equations connect
Lead-to-Customer Rate = Qualification Rate × Qualified-Lead-to-Customer Rate
In our example:
40% × 20% = 8% raw lead-to-customer conversion.
CAC = CPL ÷ Lead-to-Customer Rate
Therefore:
£80 ÷ 8% = £1,000 CAC.
3. Improvement outside Google Ads can change allowable media cost
Suppose CPL remains £80 but the sales team improves its qualified lead-to-customer rate from 20% to 30%.
The overall lead-to-customer rate becomes:
40% × 30% = 12%
CAC becomes:
£80 ÷ 12% = £666.67
No change was made inside Google Ads, yet customer acquisition economics improved by more than 33%.
4. Qualification improvements can be equally powerful
Now keep the 20% qualified-lead-to-customer rate but increase qualification from 40% to 60%.
Overall conversion becomes:
60% × 20% = 12%
CAC again falls to:
£666.67
This tells you something important:
The highest-value optimisation opportunity may sit in targeting, qualification, landing pages, CRM or sales — not necessarily in CPC or bidding.
5. Conversion rate and CPC still matter
You should still understand the media side of the model.
For example:
CPL = CPC ÷ Click-to-Lead Conversion Rate
If CPC is £6 and 10% of clicks become leads:
£6 ÷ 10% = £60 CPL.
If landing-page conversion improves to 12%:
£6 ÷ 12% = £50 CPL.
Now combine that £50 CPL with an 8% lead-to-customer rate:
£50 ÷ 8% = £625 CAC.
6. Build the complete model
| Stage | Core metric | Strategic question |
|---|---|---|
| Traffic | CPC | What are we paying to access relevant demand? |
| Lead capture | Click → lead CVR | How efficiently does traffic become an enquiry? |
| Lead economics | CPL | What does each raw enquiry cost? |
| Qualification | Qualification rate | How much enquiry volume has genuine commercial fit? |
| Sales | Close rate | How effectively does the business convert suitable leads? |
| Customer acquisition | CAC | What are we paying for an actual customer? |
| Economics | Contribution after media | What economic value remains? |
7. Model the weakest variable
Do not assume the media metric showing the biggest percentage change is the economically most important variable.
Ask:
If this variable improved by 10%, how much would customer acquisition economics change?
That might reveal that improving qualification or close rate is worth far more than shaving another 5% from CPC.
8. Economics calculator
Lead generation economics model
Interactive decision
Campaign CPL is £75. Qualification is 20%. Qualified leads close at 10%. Analysis suggests a new qualification process could raise qualification to 40%, while Google Ads CPC reductions are expected to improve CPL by only around 5%.
Practical challenge
Build your own baseline model using:
CPC → click-to-lead conversion → CPL → qualification rate → close rate → CAC → contribution after media
Then model what happens if each major variable improves by 10%. Identify which one creates the biggest economic improvement.
Knowledge check
1. CPL is £100, qualification rate is 50% and half of qualified leads become customers. What is the implied CAC?
2. Why can improving sales close rate materially change allowable CPL?
3. CPC remains £5 while click-to-lead conversion improves from 5% to 10%. What happens to CPL?
4. What is the strongest reason to build a full lead economics model?
Key takeaway
Google Ads lead generation is an interconnected economic system. CPL matters, but its value depends on qualification, close rate, customer contribution and every stage connecting the click to the customer.