Confusing advertising “kills” effectiveness, according to new analysis from Kantar, which finds ads that are hard to follow fall into the bottom 32% of all UK advertising for effectiveness.

The study compares 35 “winning” campaigns against 114 other ads featured in Marketing Week as part of ‘The Works’ study, an ongoing partnership with Kantar and the Advertising Association. Kantar finds the winners rank in the top 36% of UK ads for being easy to follow, a factor closely linked to stronger effectiveness and higher levels of brand trust.

The additional analysis is published as part of ‘Trusted Advertising: How to Harness the Power of Trust in Your Brand’, a new book by Advertising Association communications director Matt Bourn and chair of the Committees of Advertising Practice James Best CBE, released today (3 February).

The book examines trust in advertising from multiple angles, including how trust has evolved in the 21st century and the creative techniques that help brands build trust.

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The chapter draws on four years of data from The Works partnership. The study asks 750 consumers to share their views on the top-performing ads during the period, while also tracking facial expressions and eye movements to understand emotional and visual engagement. Each month focuses on a different media channel on a rotating basis.

Previous winners of The Works include Tesco for its back-to-school print campaign, Weetabix for its “tongue-in-cheek” radio ad and Amazon for its 2025 ‘Moving Day’ cinema campaign.

Kantar’s analysis shows the commercial potential of the winning ads significantly outperforms the average achieved by the others, both in the short and long term.

“The winners sit in the top third of UK ads for short-term sales, whilst the others fall toward the bottom third,” explains Lynne Deason, head of creative excellence at Kantar and author of the chapter.

A similar pattern appears in long-term potential, with winners landing in the top 31% of ads, compared to the bottom 37% for the rest.

Meanwhile, emotional resonance is a “hallmark” of the winning campaigns. Ads featured in The Works generated strong emotional responses, including joy, nostalgia, empathy, surprise, sadness and laughter, and ranked, on average, in the top 9% of UK ads for humour.

For example, a magazine ad for oat company Quaker landed in the top 1% of all UK ads for “credibility” in May 2025, by using self-deprecating humour to highlight its imperfections, calling itself the “bumpy, messy reality of breakfast”.

Similarly, Nationwide broke category conventions by using humour to position itself as the “antithesis” of other banks, landing it in the top 8% of all UK ads for its 2024 TV ad ‘in your best interest’.

The winning ads also perform strongly on branding, making it easy for audiences to recognise which brand is advertising. Winners rank in the top 20% of UK ads for branding, while the others sit in the bottom 45%.

“To have any possibility of influencing future sales, your advertising needs to build predisposition to choose your brand over alternatives,” explains Deason. “People want to know which brand an ad is for, they get frustrated if it isn’t clear.”

But great creative is only half the battle, says Deason. The other half is context.

“Ads that are tailored to the medium and the moment perform better. They avoid the disconnect – and scrolling thumbs that kick into action – that happens when an ad feels like an intrusion, when it feels like an unwelcome interruption rather than an enjoyable part of it.”

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In 2024, M&S clothing and Innocent Drinks successfully used Instagram to earn and retain attention by playing on emotions and using humour. M&S landed in the top 5% of all UK ads for relevance and the top 1% for enjoyment, while Innocent placed in the top 3% for enjoyment.

Deason notes that the ongoing study demonstrates the factors needed to make a trustworthy ad, including “emotional resonance, enjoyment, likeability, brand cues, focus and fit” in both content and context.

“Over time, a set of consistent themes has emerged from these top performing campaigns. These are not just trends; they are principles that can guide marketers and their agency partners in creating advertising that connects, converts and endures,” Deason adds.