Do TV ads "wear out"?

Broadly speaking, the response generated by a TV ad doesn't change much over time. True "wearout" of a TV ad is rare, and many TV ads could have a longer useful life than advertisers realize. The one real exception to this rule has to do with ads that focus on product news. Such ads will become less effective over time, because the people who are receptive to the message will be persuaded quickly, while those who are not receptive will not be won over by repeated viewings. Saturation of media weight over a short space of time can also create the impression of ad wearout; however, in such cases it may be the media buying strategy, rather than the effectiveness of the specific execution, that needs to be reviewed.

Advertisers often ask us how many GRPs they can put behind an ad before it "stops working." They also wonder if past copy can be rerun or if it has no remaining value. These are important financial issues for them. Producing TV ads is expensive and requires a long lead time. Airtime may need to be booked months before actual airing, and an assessment of the number of ads required needs to be made early.

How might TV ads wear out?