Double Jeopardy
Definition
Brands with less market share have so because they have far fewer buyers, and these buyers are slightly less loyal (in their buying and attitudes)
Brands with less market share have so because they have far fewer buyers, and these buyers are slightly less loyal (in their buying and attitudes)
S.D.
21 March 2025
To answer this question, it is important to keep in mind that the purchase funnel suffers from one key limitation, which is the risk of placing excessive emphasis on the middle and bottom of the funnel (driving consideration and conversion), overlooking the strategic importance of the top of the funnel, where wide-reach marketing tactics should be deployed to attract all types of buyers, including non-buyers – a vital requirement for brand and market growth. Influencers, like social media campaigns in general, tend to appeal to customers at more advanced stages of the purchase funnel, simply because: i) ‘followship’ and social media activity/engagement skew opposite to buying behaviour, with most users interacting with social media content being already existing customers/somewhat loyal to the brand behind that content; and ii) algorithms underpinning the selection of content served to people on social media (including content by influencers) automatically pick-up on existing intent and behaviour (e.g., search intent, content viewed, content interacted with, lookalikes etc.) in alignment with more advanced stages of the purchase funnel. Therefore, although influencers, like any other marketing tactic, should be used to build brand awareness (or any other top of the funnel strategy), they are feasibly more prone to impact the middle and bottom of the purchase funnel.
Working with influencers calls for two sets of strategic decisions:
Choosing influencers based on the sheer ‘size’ or their followers’ base (e.g., preferring celebrities and media influencers) to maximise reach > problematic strategy because influencers of this size have limited to no engagement for their size.
Choosing influencers based on the engagement potential and the intensity of interactions with followers (e.g., selecting everyday influencers and content creators) > also a problematic strategy because it implies repeated exposure to the brand but just with a very small (near nil) % of category buyers.
The evidence used to provide these recommendations is also based on small datasets based on single instances of influencers and social media platforms, which limits generalisability and benchmarking. Between 2018 and 2022 the Ehrenberg-Bass Institute has addressed this issue creating and analysing a unique set of data with the following characteristics:
The main findings that we extracted lead to the following recommendations:
Therefore, it makes sense to choose influencers based on their wide-reach potential.
Recommended read: Pourazad, N., Stocchi, L., & Narsey, S. (2023). A comparison of social media influencers’ KPI patterns across platforms: Exploring differences in followers and engagement on Facebook, Instagram, YouTube, TikTok, and Twitter. Journal of Advertising Research, 63(2), 139-159.
L.S
5 Sept. 2024
We do see certain repertoire markets to exhibit patterns that are closer to subscription markets (i.e., a closer loyalty towards few brands than what we would observe in other repertoire markets), however, we have seen that Double Jeopardy holds in B2B context, and in this case, baby formula also. Although the factor differences are smaller, we can still see the law applies in this category – e.g. very similar purchase frequency between the largest and the smallest brand (6.8 vs. 6.4) but there are bigger differences between their penetration figures (e.g., 26 vs. 4). We typically see the differences in purchase frequency and penetration to be larger than the examples that I illustrate here.
It is very likely that mothers would get their advice on what formula or nutrition to give to their baby from their paediatricians, thus it is very likely that bigger brands are also recommended by a lot more paediatricians, more frequently. So, in order to grow the baby formula brands, the importance of physical availability and mental availability remains true across paediatricians and parents also.
A.T.
23 November 2021
A good question. Yes, the Double Jeopardy law applies to categories and the sub-categories ‘within’ them; effectively treating the sub-categories as brands. In the broad alcoholic drinks market, product types (sub-categories) that have lower total market share will have lower penetration and somewhat lower purchase rates / loyalty (purchase frequency, share of wallet / throat). If a sub-category grows or declines it will be reflected in higher/lower penetration and associated repeat purchase rates (and all other loyalty metrics) directly in line with the Double Jeopardy law.
So yes, if Beer is declining in sales, then both penetration and purchase rate (e.g. # purchases or consumption occasions etc.) decline, penetration more so than purchase rate.
While it is definitely possible to calculate these sub-category performance metrics for the the sub-category ‘brands’ by fitting the Dirichlet Model to the overall alcohol market, unfortunately it is not a matter of a ‘simple calculation’. But it would be useful to compare over two time periods e.g. 2 years ago vs now, actual beer penetration like % of males 18-60 who drank beer in last month / not, and how many occasions or purchases including zero – so you’d get the full distribution of buyers from non, light, medium, heavy and compare then and now.
We see Double Jeopardy everywhere, from the buying of soap to the watching of soap operas. The more popular items have higher penetration (more buyers) and slightly higher loyalty metrics (both attitudinal and behavioural). Because Double Jeopardy is so widespread we call it a scientific law. But this isn’t to say we don’t know of a few conditions where the law bends:
Some brands have restricted distribution, where they are available they are quite popular but there are large areas where they unusually lack physical availability for a brand of their popularity. Private labels (retailer’s own brands) are the classic example, because they are only stocked in one retailer’s stores.
Another example are brands that have unusually high differentiation, such that they completely do not appeal to some category buyers. Pizza with pineapple on it (or anchovies) perhaps. Extremely low quality or super expensive brands may also deviate. Or unusually large (or small) pack sizes. But probably the most common surprise is how such features cause such small departures from Double Jeopardy.
A different sort of deviation is known as “change of pace”. Here lots of people buy the brand but repeat-purchase is low. A typical example is seasonal brands (e.g. easter eggs in the chocolate category).
Do you know of a deviation from Double Jeopardy? Please tell us. We’ve got bottles of Champagne to give away to those who document something new, currently unknown to marketing science.
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