Media ad sellers often have difficulty managing programmatic within their monetization strategy, but the main stimulus to change this attitude is profound knowledge of the topic.
For example, is it clear that ad requests come from the ad server, while the bid requests start from the SSP?
In the open auction, when deploying the bid request, the ad seller has a set of rules that enable buyers to make bid responses or not. This is how the blocklist works for example.
In some cases, the bid responses analyzed by the SSP are too low for the floor price, which makes it a null/invalid bid response. Null bid responses can also happen due to a lack of demand. Of course, when there are no monetization alternatives, the impression remains unsold.
Besides open auction, the SSP also allow the ad seller to create a private auction environment and define another set of offers such as dynamic or fixed price, guaranteed and not guaranteed.
Rather than fear the effects that programmatic might have on the rest of their ad business, publishers should work to optimize a channel that could actually offer more pricing competition and more scale with less work.
Other sources: see in the LinkedIn comments.