In this latest piece of the Weirdo Science series with Thinkerbell, Thinkerbell’s head behavioural science and Ai thinker Matt Plant, explores the science behind simple updates that may have benefits for your competitor. Not you.
Behavioural sciences took marketing by storm around 15 years ago, recently (and belatedly) we’ve seen some of the big guys launch their behavioural science AI agents to help nudge consumers towards a purchase. However, if you’re an aficionado of the behavioural sciences world with one or two exceptions what has been missing from the literature, and many of the experiments done in the field is the role of the brand.
The nudge world has grown up in a brand vacuum.
Arguably, two of the most well established ‘nudges’ used in marketing are ‘social proof’ (we do what other people do) and ‘scarcity’ (we value stuff more when we perceive it’s of limited supply). However, how do these nudges perform against a simple well crafted, well branded message?
That’s what we set out to find – testing the ubiquitous retail frustration ‘out of stock’.
What brand actually is (and why this matters)
Brand isn’t your logo. It’s not your “tone guidelines”. Brand is the memory structure people carry around that helps them decide fast, feel safe, and justify choices. A collective agreement as to how a company interacts with consumers at every touchpoint (clunky I know).
And the job of a brand? It’s not just to persuade now. It’s to make the next decisions easier, this purchase decision, and the next and the next and the next….
Where behavioural science gets itself in trouble
Behavioural science is brilliant at choice architecture: small cues, defaults, friction, salience. But in industry applications, it often gets over-indexed on the moment and under-indexed on the memory.
Scarcity is a perfect example. The evidence says scarcity cues can lift purchase intentions — but the effects vary wildly depending on what kind of scarcity it is (demand-based vs supply-based vs time-based) and what kind of product you’re selling (Barton et al., 2022).
The test: “Out of stock” vs “Sold out” vs “Gone fishing” (BCF fishing lures)
We ran a simple online experiment using the (wonderfully adaptable) Ideally platform on a very real retail pain point: a shopper wants a fishing lure at BCF, but it’s unavailable. Here are the three messages chosen to test with the respective justification:
- Out of stock (it’s a literal operational language)
- Sold out (it’s a classic scarcity / social proof cue)
- Gone fishing — be back soon (it’s strongly brand-coded, it’s how BCF would say it)
Here’s what happened.
Among the statements, “Gone fishing” gave the most positive impressions of the store, with 43% saying this is a store they’d be happy to buy from (vs. 16% for “sold out” and 25% for “out of stock”), and it makes a good impression on the store (again 43%).
Further, the ‘Gone Fishing’ message made people more likely to want to come back later to BCF to buy the lure, and also felt significantly less frustrating than the other two messages (only 5% vs 25% and 22%).
This suggests that the creative take on the label successfully reframed what could be a negative experience in service of the BCF brand and set up the mental architecture for a repeat purchase with the BCF brand.
These results are not real world sales data, and they are claimed intent not actual behaviour. In short this data has very real limitations. However, the results are dramatically clear.
So what does this mean for brands and behavioural scientists?
If you use nudges without brand: you may be increasing action at the cost of building for the long term. Scarcity can validate the product but disperse demand, especially if the message doesn’t also anchor the customer to you.
If you use brand without nudges: you may be charming people while failing to shape what they do next. Warmth that doesn’t create a path forward is just entertainment.
If you marry them properly: you can choose the right behavioural outcome and build memory while you’re doing it. Satisfying today and tomorrow.
Implications from our findings in an out of stock setting:
If you need basket completion for today then engineer substitution, but do it in your brand’s voice. If you prefer they purchase the exact item and you want loyalty then preserve that intent with brand-coded, time-forward framing, that don’t create dead ends in the experience (Baymard Institute, 2017/updated 2025).
So what?
We’re in the business of building brands – that means worrying about the purchase tomorrow as much as the purchase today. Therefore every sale, ideally should be done in a way that builds the brand. Ask yourself what’s branded communications to nudge demand that your competitors cant copy?
