I paid for traffic from http://www.visitorshark.com. The contract with them says that there is no guarantee that the traffic will show up on my analytics, which is your WordPress analytics. The traffic was for 6 million visitors per month. The traffic does not show up, just like they said it would not.
How can prevent this problem in the future? That is, what do I do to insure that I chose a source of traffic that DOES in fact show up on your analytics?