Does a low CTR on an ad effect the CPC for a keyword? In my example, the top keywords have a CTR of 3.4% and 3.5%, but because I have many other keywords with a CTR of 0, my text ads have CTRs of 0.4% and 0.3%. If I delete the poor performing keywords or move them to a different group, the ads is this group will gradually get a higher CTR. But does it really matter?
I understand that with the optimize option turned on, the CTR of the ad will determined the percentage served. For instance, the ad with the CTR of 0.4% has 97.1% served, while the ad with the CTR of 0.3% has 2.9% served. But is the ad CTR used for anything else?