Measurement
Part of How marketing agencies measure campaign performance
How to spot marketing agencies measurement mistakes without guesswork
A buyer's list of the measurement mistakes marketing agencies make in England, from missing baselines to dashboard theatre, with a worked pound example.
What to take away
- A buyer in England sitting in an agency pitch should ask two questions first: what is the baseline, and who owns the number after the campaign ends. If neither has a name against it, reporting drifts.
- Most measurement mistakes are commercial, not technical. A missed sales call, a lead that never reached the CRM or a report arriving three weeks late costs more than a tracking gap.
- One inclusion rule applies to this lista mistake counts if it changes a decision a client would otherwise make. Cosmetic reporting quirks do not make the cut.
- Geography matters. Data and direct marketing rules apply across the UK, but budgets, sectors and client expectations differ between England, Scotland, Wales and Northern Ireland, so check where your audience sits.
Which baseline mistakes show up most often?
Reporting often opens with a percentage uplift and no starting point. Without a stated baseline, a percentage uplift could mean anything. Ask for the previous period, the source system and the pull date.
Baseline questions to ask
- Previous period figures
- Source system named
- Pull date stated
- Lead definition agreed
- Form fills vs enquiries
Another gap is the definition of a lead. Sales teams count enquiries that reach a person; dashboards sometimes count form fills, and the two numbers then diverge all year. Agree those definitions before work starts, which is what the marketing agencies measurement and reporting guide 2027 covers in detail.
Where does attribution go wrong?
Last-click attribution flatters whichever channel sits nearest the sale. A buyer who reads three articles, attends an event and then searches your brand gets credited to the final search, and the earlier work disappears.
Agencies can still use simple models, but they should name the model and the reason for it. Where a client sells through partners or field sales, offline touches need a place in the model.
Do privacy rules change what can be measured?
The ICO direct marketing guidance sets out how consent, legitimate interests and opt-outs apply to campaign activity, and it is worth reading before agreeing a tracking plan. An agency promising full-funnel visibility without addressing consent is heading for a rebuild.
The Data (Use and Access) Act 2025 changes parts of the UK data framework, so review any measurement plan against it rather than copying an old proposal.
What does dashboard theatre look like?
A dashboard with twenty tiles and no decision attached is decoration. Good reporting answers a question the client already has: which channel produced pipeline last month, and what changes next month.
For a worked example, a client paying £4,000 a month for agency services might get a report covering eleven channels. If three channels produce qualified pipeline, the other eight still consume budget, so a short weekly note on those three beats a monthly deck.
If your reports are hard to act on, the marketing agencies reporting dashboard in England guide shows what a usable layout looks like.
How should an agency prove the work paid?
Revenue is the cleanest test, but it takes time. In the meantime, use leading indicators the sales team already trusts, such as qualified meetings booked or proposals issued.
Agree the number before the campaign starts. A figure chosen after the results arrive is not evidence.
What about industry-wide changes?
Measurement expectations move when the market moves. When ISBA welcomed the ITV ad accessibility mandate, it signalled that accessibility and audience reach are becoming part of how campaigns are judged. An agency reporting on a narrower world than its clients operate in will miss that shift.
Common questions
How many metrics should a monthly report include?
Few enough that someone reads them. Three to seven measures tied to decisions suits most English clients; more tiles rarely mean more insight.
Should I accept a percentage uplift with no baseline?
No. Ask for the prior period, the source system and the pull date. If the agency cannot supply them, treat the number as unverified.
Who owns the measurement plan?
The client owns the commercial questions and the agency owns the method. Both should sign off the definitions before work begins, then review them when the campaign changes.
Does GDPR stop an agency tracking campaign performance?
No. It changes what you can collect and join. Check the lawful basis for what you collect, then document it before agreeing the plan.
