There probably wasn't any logic to it. It was probably the equivilant of when a PM or not technical person asks a developer, "Can't we just put in an IF statement?"

this skit is very apropos https://www.youtube.com/watch?v=BKorP55Aqvg

> Just out of curiosity, how would turning on a web cam determine if a visitor saw an ad or not? I'm missing the logic.

Well, at a rough cut, it could verify that there was a client system with a person in front of it.

With more work you could maybe use eye-tracking, reflections, etc., to get a more reliable indication of whether the ad was visible to the user.

You can very easily implement eye tracking to determine where they are looking.

Possibly, but that doesn't seem like it would produce very reliable data though.

The last thing advertisers want is reliable data-- that would just prove how useless the advertising was!

It wouldn't, but one can sense some logic behind that question in this context. Additionally, advertisers are very familiar with dealing with heaps of unreliable information.