Your ad is not failing. You are just running too few.
Ad fatigue is what happens when the same ad shows up until people stop seeing it. Week after week the click cost climbs, and most founders blame the creative when the real problem is volume.
The fix is simple: put more fresh ads in rotation so no single one wears out. A new batch every 7 days, UGC videos, social ads and product images, and you only review, approve and launch.
Save this for your next ad review and send it to the founder who keeps tweaking one ad.