The ad returned 3.8 ROAS for two weeks. You touched nothing. Halfway through the third week it fell to 1.9.
The first reflex is usually to change the targeting, cut the budget, or rebuild the campaign.
All three are usually wrong. The problem is that the creative has fatigued.
What is creative fatigue?
As the same audience sees the same ad over and over, the ad loses its effect. People recognise it, their eye slides past, they don’t stop.
The platform doesn’t tell you “your ad is tired”. It tells you in the metrics — but you have to know where to look.
The three signs of fatigue
1. Frequency rises, CTR falls
Frequency is the average number of times one person has seen the ad. On its own it means little; you read it alongside CTR.
- Frequency has gone 1.8 → 3.4
- CTR has fallen 1.9% → 0.9%
If both are happening at once, fatigue is certain. The audience is seeing the ad but no longer clicking.
Threshold: in e-commerce, pay attention above a frequency of 3 and step in above 4.
2. CPM is flat, CPC is rising
If CPM (cost per thousand impressions) has stayed the same, the platform is still selling you reach at the same price. But if CPC (cost per click) is rising, you are getting fewer clicks from the same impressions.
That is not a targeting problem. The ad itself is no longer interesting.
3. Thumb-stop rate is falling
On video this is the earliest signal. The 3-second view rate shows whether people are stopping their scroll.
- Good: above 30%
- Acceptable: 20-30%
- Fatigued: below 15%
Thumb-stop can fall while the other metrics still look fine. That gives you a few days of early warning.
Fatigue, or audience exhaustion?
The two get confused, but the fixes are different.
Creative fatigue: show the same audience a new creative and the metrics recover.
Audience exhaustion: the new creative delivers the same weak performance. Here you need to widen the audience.
The practical way to tell them apart: put a single new creative alongside the tired ad, to the same audience. Wait 3-4 days. If the new creative is clearly better than the old one, the problem was the creative.
When to step in
Don’t wait until the ad collapses. By the time it does, you have already lost a week of budget.
A practical rule: at least one new creative enters the test pool every week. Scale what works, switch off what doesn’t. That way, when the winning ad fatigues, its replacement is already waiting.
What “new creative” does not mean
These do not count as new creative and will not fix fatigue:
- Changing the colour of the same video
- Rewording the headline slightly
- Cropping the same image to a different size
What fixes fatigue is a new angle: a different problem, a different hook, a different narrator, a different format.
Five ads selling the same product can make people buy for five different reasons: price, speed, trust, status, convenience. Try all five.
Checklist
Once a week, five minutes:
- Is there an ad set with frequency above 3?
- Has any creative’s CTR fallen more than 30% in the last 7 days?
- Is CPC rising while CPM is flat?
- Has the 3-second view rate on video dropped below 20%?
- Is there a new creative going into the test pool this week?
If the answer to the last question is no, the drop is already on its way.