Paid ads are the one lever that turns money directly into attention — which makes them powerful and dangerous. Powerful because you can reach exactly the right people on demand. Dangerous because you can burn a month's budget in a day if you don't understand the funnel you're feeding and the maths that tells you if it's working.
The funnel
- Awareness — people discover you exist (top: reach, impressions).
- Interest / Consideration — they engage, click, follow, ask (middle).
- Conversion — they buy (bottom).
- Retention / Advocacy — they buy again and refer (the part most people ignore, where the profit is).
Ads reveal the funnel's leaks
If you send 1,000 paid clicks to a page and nobody buys, the ad isn't the main problem — the offer, the landing page, or the trust is. Ads don't fix a broken funnel; they expose it faster. Fix the leak before you scale the spend.
The three numbers that matter
- CAC (Customer Acquisition Cost) = ad spend ÷ customers won. Spend KES 10,000, win 20 customers → CAC KES 500.
- ROAS (Return on Ad Spend) = revenue from ads ÷ ad spend. KES 40,000 revenue from KES 10,000 spend → ROAS 4×.
- Break-even ROAS = 1 ÷ your margin. At a 25% margin you need ROAS above 4 just to not lose money.
Compare CAC to lifetime value
A CAC of KES 500 looks expensive for a KES 300 sale — until you know the average customer buys six times. Judge acquisition cost against lifetime value (next module), not a single purchase.
Test like a scientist, not a gambler
Don't hand a platform KES 20,000 and hope. Start with a small budget, change one variable at a time (audience, or creative, or offer — not all three), give it enough time and data to read, then double down on the winner and cut the loser. Marketing on paid channels is a loop of small bets, not one big gamble.
Check your understanding
You spend KES 10,000 on ads and earn KES 30,000 in revenue. Your profit margin is 25%. Are the ads profitable?
Check your understanding
1,000 people click your ad and land on your page; almost none buy. What's the right first move?
Exercise · try it first
Plan a disciplined KES 5,000 test campaign. (1) Define the ONE objective and the single audience you'll target. (2) State the ONE variable you're testing (e.g. two headlines, everything else identical). (3) Do the maths up front: your price, your margin, and therefore the break-even ROAS and the CAC you can afford. (4) Write the stopping rule — what result makes you scale, and what result makes you kill it — BEFORE you spend, so emotion doesn't decide.