Maddie Lightening speaks on misreported ROAS, account structure chaos & AI mistakes

Maddie Lightening, head of paid media at Hallam, joined me to talk through the mistakes, lessons and mindset shifts that have shaped her career in PPC. With more than a decade of experience across search, social, programmatic, digital out of home and ABM, she shared a candid look at the realities of leading paid media in a fast-moving industry.
The reporting mistake that doubled performance
One of Maddie’s early mistakes involved misreporting performance due to account currency differences. Working with an Australian billing setup while reporting in GBP, she unknowingly halved the reported results because conversion values were being translated. The issue only surfaced after comparing platform data with CRM figures, revealing that performance was actually twice as strong as reported, highlighting how easily technical setup details can skew results.
When legacy account structure becomes a problem
A more complex challenge came from a travel client running an outdated, highly granular account structure with thousands of campaigns. While this “2016-style” setup had previously worked, it clashed with modern AI-driven bidding and data consolidation approaches, making it harder to optimize performance and diagnose issues when results began to decline.
Why timing matters as much as strategy
Maddie explained that although the team had planned to restructure the account, they delayed it to avoid disrupting peak season. When performance dropped in January, they were forced to make multiple changes quickly, which increased pressure and complexity. In hindsight, starting the restructure earlier would likely have reduced risk, showing that delaying necessary changes can sometimes be more damaging than acting sooner.
The pressure of fixing performance in real time
As performance declined during a critical period, the client became understandably concerned, especially given how much of their annual budget was tied to peak months. At the same time, audits and internal reviews added pressure, making it one of the most challenging moments of Maddie’s career, but also reinforcing the importance of collaboration, support and staying focused on solutions rather than panic.
How a max CPC cap helped reclaim control
One key fix involved regaining control over rising CPCs by applying a max CPC cap through portfolio bidding strategies, even while using automated bidding. This approach reduced CPCs significantly without harming performance, demonstrating that advertisers can still guide AI-driven campaigns by applying the right constraints rather than relying on full automation alone.
Why banning AI is the wrong move
Maddie also highlighted a broader industry mistake: refusing to adopt AI altogether. She recalled working at an agency that banned AI tools and automation, which she believes limits growth and puts teams at a disadvantage. Instead of resisting AI, she argues that marketers should learn how to use it strategically while maintaining oversight.
Better prompts lead to better AI outputs
A key takeaway on AI usage is that results depend heavily on input quality. Maddie emphasized that vague prompts produce weak outputs, while detailed context—such as goals, audience and structure—leads to far more useful results. AI should be treated as a support tool that enhances human work, not replaces it.
Why curiosity still matters in PPC
Maddie stressed the importance of experimentation, encouraging teams to test ideas even when outcomes are uncertain. Her philosophy—“test and learn”—reflects the idea that even unsuccessful experiments provide valuable insights that can inform better decisions in the future.
Small mistakes are not career-ending
She also addressed everyday mistakes, such as sending the wrong report to a client, noting that while they may feel serious in the moment, they are usually easy to fix. The key is to take accountability, correct the issue quickly and keep perspective rather than overreacting.
The bigger lesson for paid media teams
Across all her examples, Maddie reinforced that success in PPC comes from adaptability, continuous learning and a willingness to challenge existing approaches. Whether dealing with account structure, automation or performance issues, the ability to evolve is what separates strong teams from the rest.
Final takeaway
Ultimately, Maddie’s experience shows that mistakes, when handled correctly, can lead to stronger strategies and better performance, and that staying curious, proactive and open to change is essential for long-term success in paid media.


































































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