By Ed Dalgleish, Planning Director, Guy & Co
“Assumptions are dangerous things” wrote Agatha Christie, and she’s not wrong – they might just murder your brand.
All too often marketers fall back on comfortable conventions as they give us a shortcut to what’s “obvious” about an audience, category or challenge. But often, they do the opposite. They shrink our field of vision.
But worst of all, they take away the unfair advantage we’re ultimately trying to create for brands.
So why do assumptions so often lead us astray?
I believe it’s at its most common – and most dangerous – when the motivation driving the effort is more concerned with not getting things wrong, than pushing for what’s right. Prioritising avoidance of error leads to safety over originality. Here’s some ways we can stay ahead by challenging our assumptions:
Comfort is a category trap
Every category has its comfort blanket. It’s why you see the same scenes again and again: the polite pensioner in the conservatory or the moody whisky in a dimly lit bar.
But “safe” is also how brands become interchangeable. The moment a marketer feels certain – we know this category, we know this brief – that’s exactly when the work stops being interesting.
The only way to have good ideas is to have lots of ideas, and assumptions can limit our field and range of thinking.
Dan Wieden had a healthier attitude: “Walk in stupid every morning.” Ask the obvious questions that assumption would have you avoid. That’s where better thinking can hide.
The danger in the data
Data should keep us honest. But when we look for confirmation, we erase exactly the odd details that could unlock a new way to see things.
Crabtree’s Bludgeon warns that ‘no set of mutually inconsistent observations can exist for which some human intellect cannot conceive a coherent explanation, however complicated’.
One way to avoid the pitfall is to look for anomalies not reassurance – the behaviours that stick out, the surprising comments, the unexpected audiences. These irregularities are often early signs of bigger shifts.
Data is always a rear-mirror view – facts can only describe what has happened, not what will.
The risk of change
As an industry, we’re often bored of ideas long before our audiences. But it’s clear that creative consistency matters.
Fresh IPA and System1 analysis show that brands with strong, recognisable creative foundations reliably produce better-performing advertising and larger business effects over time. But this gives a more nuanced assumption to navigate – consistency isn’t repetition; it’s maintaining distinctive cues while exploring braver creative territory.
It’s no secret that consumers are in constant flux. Why do we so often assume that doing the same thing will get different results? Do you know what happened to your audience since the last time you spoke to them? Especially if you’re working on an annual plan.
Just look at how quickly consumer methods of research and discovery have moved. UK social commerce is set to double to around £16bn by 2028, with TikTok leading the way. Old assumptions no longer hold up. When environments change, assumptions expire fast.
Some of the strongest recent work has come from brands willing to reject the assumptions of their category’s rules.
Take Tamdhu. Instead of leaning into the usual whisky atmospherics, it collaborated with a photomicrographer to capture the liquid at 43–46× magnification, turning it into abstract, vivid art. A challenge to convention that still respected brand truth.
Or Glenmorangie. ‘Misbehaving’ with Harrison Ford in a humorous series set in the Highlands broke from whisky’s typical solemnity. It stood out because it didn’t follow the expected script – and wasn’t afraid to break the assumptions.
But it’s not about refusing change. Past experience still matters. It’s about avoiding the hubris of thinking we know it all already because we’ve seen it all before.
So what do brands need instead?
A healthier relationship with assumptions.
It starts with creating a culture that notices when thinking becomes too tidy. Treating curiosity as a discipline and prefers questions with promise over comfortable answers.
That means looking for anomalies rather than averages. Asking “stupid” questions out loud. Stress-testing whether an idea is genuinely distinctive or just the polished version of what everyone else will do.
It also means protecting things that shouldn’t change. Values and positioning create clarity; distinctive brand assets give you the freedom to explore without losing yourself. Hold those steady, experiment everywhere else.
Quick, cheap tests in real attention environments teach you more than another round of polite alignment.
The brands that win don’t rely on assumptions; they rely on habits. Curiosity. Challenging their own logic. Spotting anomalies. Protecting distinctiveness while pushing creatively.
As Agatha warned, assumptions are dangerous things. So treat them with caution and question them before they question your results.
