Re: Product listing ads[ Edited ]
October 2016 - last edited October 2016
shopping-ads (product-listing-ads) are part of a
highly dynamic, competitive advertising auction.
results in the auctions are mainly determined by quality and the bid --
as quality, bids, and advertiser's campaign settings related to targeting
and other factors such as ratings, reviews, merchant-promotions, etc.,
fluctuate, the auctions may show different results.
user-behavior may also be taken into account with respect to ad relevance
and quality; a somewhat common occurrence is for shopping-ads to slowly
disappear if little or no positive action is taken over time, as ads are shown
for specific search-terms.