Marketing Works! (And Here’s the Proof)

Most businesses treat marketing as a cost. The good ones treat it as an investment. The difference between those two mindsets is, very often, the difference between a business that grows and one that stalls.

The old line still gets quoted in boardrooms: “Half my marketing works, I just don’t know which half.” It’s a nice quip — and a lazy excuse. In an age of tracking, attribution and AI, that mystery is largely solved. The businesses still hiding behind it are usually the ones who never committed to marketing properly in the first place.

So let’s deal in facts, not faith.

Marketing pays back — measurably. Nielsen’s analysis of thousands of campaigns puts the average return at roughly €1.09 for every €1 spent, and over €2 for the most effective quarter of advertisers. That’s not a rounding error. That’s a return most businesses would bite your hand off for on any other line of the P&L.

It compounds at a national level. McKinsey found that advertising fuelled roughly 15% of GDP growth across the major G20 economies over a decade, because it generates genuinely new business. Marketing doesn’t just move your slice of the pie — it grows the pie.

Cutting it is where the real money is lost. Study after study of past recessions shows the same pattern: businesses that cut advertising in a downturn lose sales during it and for years after, while those who maintained or increased spend took market share and came out ahead. When competitors go quiet, the room is yours — if you keep talking.

Spend it in the right balance. The most robust evidence in the industry — Binet & Field’s analysis of nearly 1,000 campaigns — points to a roughly 60% brand-building / 40% lead-generation split for established businesses. But it shifts with your stage: an early-stage business should lean hard into lead generation (think 90/10), and dial up brand as it matures. Lead gen brings the sales this quarter; brand is what makes every future sale cheaper.

So here’s the BA playbook:

• Commit a real budget — and 3% is the number. Start at 3% of sales. On €1,000,000 of sales, that’s €30,000 a year. Not 1%, not “whatever’s left over” — 3%. If that figure makes you wince, that’s not a reason to spend less; it’s a sign you’ve been under-investing and calling it prudence. Adjust upward as you grow — big brands and online players push to 12–15% and earn it back many times over — but 3% is the floor you build from. That’s the answer, whether it’s comfortable or not.
• Put someone in charge of it. If you don’t already have a marketing function, build one — employ someone full-time or part-time to own it, or appoint an external consultant who takes full responsibility. Marketing without a clear owner drifts, and drifting budgets are the ones that get blamed for “not working.”
• Write a proper annual plan. Split it offline and online, broken down month by month. Agree it, approve the budget, then bring in specialist expertise to execute.
• Don’t expect one person to do it all. Marketing is now hyper-specialist — your Facebook expert may be useless at SEO or Google Ads. That’s normal. Build the right mix.
• Use AI everywhere — and understand it’s changing the game right now. AI is transforming how marketing plans are built, how budgets are modelled, how campaigns are executed and how returns are measured — faster and cheaper than ever before. The businesses that lean into it will pull away from those that don’t. Use it to sharpen the plan, model the spend, execute and calculate the return. (A full piece on this is coming.)

And the question I ask every marketer — “what happens if we double or halve the spend?” — should have a confident, evidenced answer. If it doesn’t, that’s the first problem to fix.

Marketing isn’t a leap of faith. The numbers are in. As one of the best in the world at it would say — Just Do It.

Marketing Works.