According to The PreTesting Company, television ad campaigns are too long and lead to weariness on the part of viewers. Using their MediaCheck system, PreTesting found that after about two weeks into a five-week campaign TV watchers grew uninterested in watching the same spot over and over again. Most of the ads in the study, the details of which are here, were for staple-type items or fast food dining.

When you think about it this makes sense. After all, people are increasingly watching fewer and fewer reruns of actual programming why would they continue to watch what amount to reruns of ads? The guidance from the study seems to be that media planners need to cut their campaigns in half to avoid viewer burnout.