Most marketing plans are built on a quiet assumption: if an ad was delivered, it did some work. The dashboard says 4.2 million impressions, so 4.2 million moments of influence must have happened somewhere.
They didn't. An impression is a record that an ad loaded. It says nothing about whether a person looked at it, read it, or would remember it tomorrow.
For a soft drink, that gap is tolerable. For a patient deciding whether to ask a surgeon about a new procedure, it is the whole game. The message has to be seen, read, and internalized … well enough to survive until the moment it matters, which is often weeks later, in an exam room.
The impression is a very low bar
The industry's own definition shows how low. Under the Media Rating Council standard, a display ad counts as "viewable" when half its pixels are on screen for one continuous second. Nobody has to look at it. An ad playing muted in a corner counts the same as one a reader stopped to study.
Eye-tracking data fills in the rest. Lumen Research estimates that of 1,000 desktop display ads bought, roughly 80 get looked at, for about 1.3 seconds each. That works out to around 110 seconds of human attention per thousand impressions. Lumen has also found people are far more likely to remember a brand when they look at an ad for more than two seconds, a threshold most display never reaches.
This is why frequency targets keep climbing. Herbert Krugman’s original “rule of three” argued that three exposures could be enough: one to notice, one to understand, one to decide. That logic assumed each exposure was actually experienced. When most exposures are glanced at or missed entirely, marketers compensate by buying more of them. Pharma media plans routinely aim for far higher frequency than Krugman's three, and much of that extra frequency is paying for impressions that never registered.
What it takes to be internalized
Getting seen is step one. Getting remembered is a different problem, and the research on it points consistently in one direction: people process paper more deeply than screens.
Reading research. A 2024 meta-analysis from University of Valencia researchers pooled 49 studies and found readers comprehended less on handheld screens than on paper, a pattern known as the "screen inferiority effect." The effect is modest per reading, and earlier work found it roughly doubles when the screen is a computer. One leading explanation is the "shallowing hypothesis": we use screens for fast, skimming engagement, so we bring that mindset to everything we read on them.
Advertising research. A neuromarketing study by Temple University's Center for Neural Decision Making for the USPS Office of Inspector General put physical and digital ads head to head. Digital ads were processed faster. Physical ads held attention longer, produced a stronger emotional response, and were remembered better. They also activated the brain region tied to valuing and wanting a product. A follow-up study found that in mixed campaigns, what mattered most for memory was simply that a physical piece was included somewhere in the sequence.
The pattern is the same across both bodies of work. Screens win the quick glance. Paper wins the considered read, and true consideration is what turns a message into motivation to act.
Why healthcare can't run on glances
In healthcare, the gap between a fleeting impression and an internalized message is wider than anywhere else in marketing. Three reasons:
The decision is considered, not impulsive. Nobody makes a healthcare decision on a whim or because of a simple banner. Specialty therapy is considered over weeks or months.
The action happens offline, later. The moment of truth is a conversation with a physician. The patient needs to walk in remembering the treatment option, the questions to ask, and how to ask them.
The message is complex. Eligibility, risks, and how one option differs from the alternative do not fit in a one-second glance.
A physical piece does something a pixel cannot: it stays. It sits on the counter. It gets handed to a caregiver, circled, and brought to the appointment. Its useful life is measured in weeks, not seconds.
Measure what matters
Of course, theory is one thing, metrics are what matters. But which ones? Efficiency metrics are important channel metrics, but can be shortsighted. A cheap CPM becomes expensive quickly if the message doesn’t land with a qualified audience. Activity metrics can be a sign that users engaged with a message, but doesn’t tell you if minds were changed. What matters is simple: did the right person read, internalize and act on your message? When measurement focuses on qualified patient / doctor conversations … the formula shifts. The media plan changes. Fewer, better-targeted touches which slow people down.
It’s not about reaching more people cheaply, but reaching the right people most effectively.
Sources
Altamura, L. (2024). Turning the Page: What Research Indicates About Print vs. Digital Reading. Oklahoma Education Journal. Summarizes the 2024 meta-analysis (doi:10.1037/edu0000830).
USPS Office of Inspector General. Enhancing the Value of Mail: The Human Response (2015).
Temple University Fox School of Business. Consumers more likely to recall printed ads than digital ones (2017).
Lumen Research. Attentive seconds: one currency to rule them all?
Lumen Research. The future of Facebook is Lumen
PPC Land. Viewability (MRC display standard).