Why is it so hard to convert on forums?

Absolutely 100% correct Photon. Additionally, a forum is a long tail keyword factory that's built slowly over time by member participation. If a good forum admin is known by his members and carefully selects ads based on the forum's members, you'll get clicks from members and guests alike. Sometimes if a forum makes enough controversy, you'll get lurkers who will click on ads because they are already lurking so they must be interested in something. In another life I was a guitar player in a punk band and when you're in a band, you learn over those kids that say they hate your music are lurking around to see what you're doing. As a successful marketer or promoter it's essential you know that success is a love/hate business and being able to perform on a regular basis with a dash of controversy will sell whatever your pimping whether it be clicks or ipods.

 

I think it is from artificially boosted ad impressions from users browsing. You might see 1k ad impression but that will be from 100 users.

 

the main problem of the forums is that they have continues visitors.

placing adsense different places on every page load can help