Although publishers often accept takeover ads and stalker ads because they command high rates, these ads can backfire for both advertiser and publisher, particularly when the ads interrupt navigation or cover content.

"That's really annoying," said Erin, a 25-year-old account manager, wryly waiting for a takeover ad to finish rendering at tvguide.com. "I was trying to read the page."

User-initiated video, audio and rich media are clearly the way to go in order to avoid this sort of response.

Auto-launched audio infuriates users

For Steve, the user pictured in this test, his first experience at abc.com turns negative when audio automatically launched.

A more subtle consequence of poor ad experience is the waste of an opportunity to engage the user. In our tests, six users had 12 opportunities to express interest in ad content, but interest in ads was only expressed three times.

Val, a 30-year-old bank officer, repeatedly answered "no" when asked if she had a response to any of the ads, explaining, "I already know what I want." The many ads she saw during the test failed to engage her attention, regardless of how intrusive they were.

Next: Users adapt behavior