Most marketers can't answer this question in one sentence. Ask a room full of B2B marketers what marketing is actually for, and you'll get a dozen different answers: brand awareness, lead generation, demand creation, pipeline, content. All of these are activities. None of them are the purpose.

Here is the direct answer: marketing exists to build and maintain mental availability and physical availability for a brand, so that when a buyer enters the market, your brand is the one they think of and the one they can easily buy. That definition comes from the Ehrenberg-Bass Institute for Marketing Science, and it is the closest thing the discipline has to a settled, evidence-based answer.

Why this gets confused

Most marketers never received formal training in what marketing actually does. They inherit a job title, a set of channels, and a quarterly target, and they back into a definition of marketing from whatever their function happens to measure. A demand gen marketer defines marketing as pipeline. A brand marketer defines it as awareness. A content marketer defines it as engagement. Each is describing their slice of the job, not the job itself.

The research, plainly stated

Byron Sharp's How Brands Grow, built on decades of Ehrenberg-Bass data across categories and countries, makes the case that brands grow primarily by acquiring new, light, often indifferent buyers, not by deepening loyalty among existing ones. Buyers in any category, B2B included, are mostly out of market most of the time. The brands that grow are the ones that are easy to think of and easy to buy the moment a buyer's need appears.

Les Binet and Peter Field's work, analysed across hundreds of IPA-effectiveness case studies, adds the other half of the picture: brand-building activity (reaching the 95 percent not yet in market) and activation activity (converting the 5 percent who are) do different jobs, on different timelines, and both are necessary. Most B2B marketing budgets are skewed almost entirely toward activation, chasing the small in-market group with demand gen tactics, while doing almost nothing to build availability with everyone else.

What this means for how you spend your time

If marketing's purpose is mental and physical availability, then the test for any marketing activity is simple: does this make us easier to think of, or easier to buy, for more potential buyers? A webinar that only reaches people already evaluating vendors fails that test for most of its theoretical audience. A piece of content that builds a distinctive, recognisable point of view, seen by people who are not yet buying anything, passes it.

This is not an argument against lead generation. It is an argument for sequencing: build availability broadly and consistently, and the in-market minority converts at a far higher rate when they do arrive, because they already know who you are.

Where to go next

This first-principles view, why brands grow, what mental and physical availability mean in practice, and how to apply it to a B2B marketing plan, is the foundation of Module 1 of B2B Marketing Fundamentals. It's free, and it walks through the evidence in more depth than a single post can.

Start Module 1 free