What Is Incrementality and Why Should Ecommerce Leaders Care?
Incrementality sounds like an analytics term.
It is really a commercial question:
What happened because we did this that would not have happened otherwise?
Why attribution is not enough
If a customer clicks a paid ad and buys, attribution connects the interaction to the order.
Incrementality asks whether the order depended on the ad.
That distinction matters most in channels that sit close to existing demand: brand search, retargeting, affiliates, CRM and some promotional activity.
A simple example
Run a campaign and 1,000 people buy.
It is tempting to call those 1,000 sales the result.
But if 700 of those customers would have purchased anyway, the incremental effect is much smaller.
The campaign can still be worthwhile. We simply need a better estimate of what it added.
How do you measure it?
The strongest methods use some form of counterfactual: holdouts, geographic tests, matched groups, lift studies or controlled experiments.
Not every business can run perfect tests, so I also use triangulation: changes in total revenue, new customers, blended efficiency and behaviour alongside channel data.
Why leaders should care
Without incrementality, businesses can overinvest in channels that are excellent at claiming demand and underinvest in activity that creates future demand.
It also affects discounting. A promotion may generate a huge sales number while paying customers to do what they were already going to do.
Do not let perfect measurement become the enemy
Incrementality can be difficult.
The answer is not to give up and blindly trust the easiest attribution model.
Even asking the question improves decision-making:
What do we genuinely think this activity added? What evidence supports that?
That is a much more commercially useful conversation than arguing over which dashboard owns the order.
If the platform reports look healthy but the commercial number does not, I can help you separate channel performance from the wider growth problem.
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