Marketing in a Minute – Episode 24 | Ahmed Moaaz
Some orders would have happened anyway. The concept of incrementality asks: how many orders exist because of the ad, really? That is the number your budget decisions should be built on.
The hardest question in advertising
If you stopped your ad campaigns completely for a month, how many of your sales would disappear? The orders that would disappear are the only ones the ads “truly brought”. This concept is called incrementality: the difference between what happened with the ad and what would have happened without it. The question sounds theoretical, but it is the most dangerous financial question in your marketing: if a third of the sales attributed to your ads would have happened anyway, you are paying a third of your budget for nothing.
Why is this different from attribution?
In the previous episode we discussed attribution: which channel deserves credit for an order that happened. Attribution answers “who touched the customer along the way?”, while incrementality answers “would the order have happened at all without the ad?”. The practical difference is huge. A retargeting ad shown to someone who already decided to buy and would have purchased in an hour claims the whole sale for itself, but its actual increment is zero. And an awareness ad that introduced you to someone who had never heard of you, then bought two weeks later through a Google search – Google claims the sale, but the real increment started with the awareness ad.
Where do “phantom” sales accumulate?
- Retargeting: it chases people who visited your site – the closest people to buying without an ad anyway. Its increment is real but far smaller than its reports claim.
- Search ads on your own name: someone searching your store’s name mostly decided to buy before seeing the ad. You are paying for a click from a customer who was coming free through the organic result.
- “Existing customer” campaigns: ads targeting your past-customer list measure “sales” a large part of which loyalty alone would have produced.
The common denominator: the closer the ad sits to the bottom of the customer journey – the near-buyers – the prettier its numbers look and the smaller its true increment.
How do you measure the true increment?
- The switch-off test: stop a channel or campaign for two weeks and watch your actual total sales, not the platform’s reports. The drop that occurs is the size of its true increment. Simple, and sometimes shocking.
- Geographic split: run the campaign in some governorates and stop it in similar ones, then compare the two regions’ sales. The difference is the ad’s net effect.
- Control groups: the big platforms offer ready-made tests that withhold the ad from a random sample of your audience and compare their behavior with those who saw it. The most accurate method available to everyone.
You do not need to run these tests constantly; once every while for each major channel is enough to learn its approximate “incrementality factor” and correct your reading of its daily reports with it.
A practical example with numbers
A store spends 12,000 EGP a month on retargeting, and its reports say it produces 60,000 EGP in sales – a five-fold return that looks excellent. It ran a three-week switch-off test: total sales fell by only 9,000 EGP during it, equivalent to about 13,000 EGP a month – not 60,000. The real math: retargeting adds about 13,000 EGP of monthly sales against 12,000 EGP of spend – a true incremental return of about 1.1 only, practically losing at any normal profit margin despite its rosy reports. The owner redirected half the budget to new-audience acquisition campaigns, and the total rose after two months even though the “platform numbers” became less dazzling.
Does this mean retargeting is useless?
No. It speeds up the decision of someone who was going to buy and catches a real share that would have been lost – but its right size in your budget is far smaller than its reports suggest. The practical rule: keep the share of retargeting and own-name ads limited (a commonly suggested reference range is 10-20% of budget, not a fixed rule that suits everyone), and direct the larger part to people who do not know you yet; they alone truly expand your business.
How do you start with the simplest possible test?
Do not start by stopping everything; pick the most suspicious item in your budget – usually own-name search ads or retargeting – and run an organized switch-off test on it:
- Record the baseline: your average total daily sales over the previous four weeks, so you have a reference for comparison.
- Stop the chosen item for two full weeks: touch nothing else during them so causes do not mix.
- Compare the averages: the difference between the switch-off period sales and the baseline is this item’s true increment.
- Calculate the decision: if its increment is below its cost, the natural place for this budget is another channel or straight savings.
- Document the result: record the date, numbers and decision, so nobody else on your team restarts the item without asking two months later.
An important note: run the test in a normal period, not during a peak season or huge promotions, so the result is not contaminated by other factors.
A common mistake: mixing testing with mood
The worst use of this idea is randomly switching off for two days whenever the numbers annoy you, then switching back on. Two days are not enough to see an effect, and repeated on-off cycling corrupts the platform algorithm’s own learning. A serious test has a defined duration, a written hypothesis and a pre-announced decision: what will we do in each possible outcome?
The ultimate goal of all this is not to doubt advertising, but to trust it genuinely. When you know each channel’s incrementality factor, platform reports become readable correctly: divide their attributed numbers by the inflation factor you measured yourself (attributed sales ÷ measured true increment) to get an honest estimate, and build your budget on solid ground instead of the shifting sand that optimistic reports sell you.
Summary
The question is not “how much did my ads sell?” but “how much did they sell above what would have sold without them?”. Measure the true increment with a switch-off test or geographic split once every while, and treat platform reports as an optimistic ceiling, not truth. An advertising pound earns its place only if it created an order that would not have happened without it.
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