Is it more profitable to reach 1 million people with one impression or 500,000 people with two impressions?
The answer might surprise you.
The answer might surprise you because there is a long-standing myth in the advertising industry that three impressions is the “optimal frequency” to maximize sales. Many advertisers interpret this data to mean reach alone cannot generate sales, frequency is required.
However, what does the evidence from marketing science and marketing practice say?
Well, the evidence on reach and frequency dating back to John Phillip Jones (1992) shows the sales response to advertising exposures is convex and “once is enough.” Thus, a single exposure is not only enough to generate sales, a single exposure actually generates the greatest sales response, with each additional exposure to the same individual (frequency) likely to produce a smaller, though still positive, sales response.
So if given the choice, the higher return strategy is not to show a second exposure (frequency) to the same individual and, instead, show a first exposure to a new individual.
A simpler way to explain the math comes from Bob McCurdy, who wrote a seminal 2017 article called “Reach vs. Frequency In The ROI Stakes.” The article discussed data from a Nielsen study analyzing three different frequency strategies – low, medium, and heavy – and calculated sales responses for each strategy.
The study corroborated the “once is enough” finding pioneered by Jones (1992) and replicated by Taylor, Kennedy, & Sharp (2009), among others.
The study found:
- 41% of buyers were “low frequency,” which means they’d been exposed to an ad 1-2 times, or 1.5x on average.
- 25% of buyers were “medium frequency,” which means they’d been exposed to an ad 3-6 times, or 4.5x on average.
- 33% of buyers were “heavy frequency,” which means they’d been exposed to an ad 7+ times, or 10x on average.
In his article, McCurdy also calculated the number of gross impressions (reach x frequency) each strategy needed to produce one point of sales growth:
- The 41 “low frequency” buyers saw 1.5 exposures on average, which equals 61.5 gross impressions (41 x 1.5). Those 61.5 gross impressions generated 31% of total sales, which means it took 1.98 impressions to produce each point of sales growth (61.5/31).
- The 25 “medium frequency” buyers saw 4.5 exposures on average, which equals 112.5 gross impressions (25 x 4.5). Those 112.5 gross impressions generated 24% of total sales, which means it took 4.7 impressions to produce each point of sales growth (112.5/24).
- The 33 “high frequency” buyers saw 10 exposures on average, which equals 330 gross impressions (25 x 4.5). Those 330 gross impressions generated 45% of total sales, which means it took 7.3 impressions to produce each point of sales growth (330/45).
The math not only makes clear “once is enough” to generate a sale, but also the “medium frequency” strategy cost 2.4x as much as the “low frequency” strategy (4.7/1.98=2.4) and the “high frequency” strategy cost 3.7x as much as the “low frequency” strategy (7.3/1.98=3.7).
Simply put, a low frequency – and high reach – strategy is the lowest hurdle to reach a set amount of sales growth.
Other single source experiments also show “high frequency” strategies reduce sales impact by showing excess frequency to the same potential buyer in a short period of time instead of reaching new potential buyers with broader targeting. The ROI from the 10th exposure is worth less than the 3rd exposure.
This collective data helps explain why reach trumps frequency and why reach maximalism over audience, time, and geography is a key strategy to profitable advertising.