What does Interstitial Ad Frequency mean ?


New Member
Hello ,
I have installed Interstitial ads in my app and checked : Visit Website,View Article,View Image and Play Video boxes to show an interstitial ads while doing these tasks , but i did not see any ad , what is the relation between the interstitial ad frequency and showing ads ?

By the way, i tried to use 1 , 30 and 60 frequency but i did not catch any difference.