The ad networks bare most of the blame because they face a moral hazard. They can either deny annoying ads and lose revenue, or accept them and push the risk of adverse events to the publisher. The publisher will respond as you describe above. Ultimately the publisher fizzles out and their ad network drops them for non-performance.
Most ad networks appear to be willing to accept trashy ads in lieu of instituting quality controls.
This is my experience in working at a publishing network that did not have its own ad server.
The ad networks bare most of the blame because they face a moral hazard. They can either deny annoying ads and lose revenue, or accept them and push the risk of adverse events to the publisher. The publisher will respond as you describe above. Ultimately the publisher fizzles out and their ad network drops them for non-performance.
Most ad networks appear to be willing to accept trashy ads in lieu of instituting quality controls.
This is my experience in working at a publishing network that did not have its own ad server.