GWI surveyed 150 marketers in the UK to explore their confidence levels in AI-generated insight.

Over a third ( 35%) of participants reported customer complaints as a result of inaccurate or misleading insights from AI, while 29% of participants said inaccurate or misleading insight had led to financial losses for their organisation and 29% reported reputational damage.

The research also explored the internal impact of inaccurate outputs, with 47% of participants saying that inaccuracies had forced teams to redo work and 54% reporting delays to decision-making.

Additionally, 84% of marketers agreed that AI makes it easier for outdated information to influence decisions, while 79% agreed they have accidentally used data that they later realised was out of date.

GWI chief insights officer Jason Mander said the findings show the business cost of acting on incorrect insight.

Mander said: “AI is only as reliable as the data behind it. Verification means knowing where an insight comes from, how the underlying data was collected and whether it’s still up to date. These checks need to be built into everyday workflows, so that when an insight informs a campaign or business decision, there’s strong evidence behind it.” 

GWI conducted the research in July 2026 using its platform. The study surveyed 457 marketing professionals across the UK, Singapore, and the US, with job roles including content marketing, creative strategy, marketing, media planning and buying, brand management, ad sales, brand partnership management, content specialist and social media.

The data will be published in a forthcoming report from GWI in November.

Kantar research published yesterday ( 29th September) suggested marketers are planning to increase their investment in AI visibility next year.