What Is the Novelty Effect in Advertising?
The novelty effect refers to the temporary boost in engagement, click-through rates, or conversions that occurs when an audience is first exposed to a new creative, format, or channel. This spike is driven by curiosity and the brain's natural attention response to unfamiliar stimuli. Over time, as the stimulus becomes familiar, performance typically declines to a more stable baseline. In digital advertising, this effect can mask the true long-term effectiveness of a creative asset, leading marketers to over-invest in new ideas that may not sustain performance.
Why Does the Novelty Effect Matter for Creative Testing?
When running A/B tests or creative rotation strategies, the novelty effect can distort results. A new ad may outperform an existing control simply because it's new, not because it's better. If you launch a test and declare a winner within the first few days, you risk basing decisions on inflated early data. This is especially problematic for platforms like Facebook or TikTok, where algorithms may initially favor new creatives by showing them to more engaged users. The effect typically lasts from a few days to a couple of weeks, depending on audience size and frequency of exposure.
How to Account for the Novelty Effect in Your Testing Process
To get reliable results, run tests long enough for the novelty effect to wear off—usually at least one to two weeks. Use holdout groups or frequency caps to compare performance after the initial spike. Another approach is to pre-expose a segment of your audience to the creative before the official test, so the novelty is burned off. In creative operations, tools like CO8 can help automate rotation schedules and track performance over time, flagging when a creative's novelty boost has faded. Remember: a creative that performs well after the novelty effect is a true winner.
Common Mistakes and a Concrete Example
A common mistake is declaring a winner based on a 48-hour test. For example, a DTC brand launches a new video ad and sees a 50% higher CTR than the control in the first three days. They scale it, only to see performance drop to control levels after a week. The initial spike was the novelty effect. A better approach: run the test for two weeks, or use a holdout group that doesn't see the new ad until week two. If the new ad still outperforms after the novelty wears off, it's a genuine improvement.