The likely answer is to do with audience biases. A survey conducted by an email marketing provider is almost certainly going to have different results to one conducted by PPC management tool, as their audiences have different skillsets and biases, skewing the results of their sample. As such, we should take the specific ranking of different strategies in these studies with a pinch of salt.
Fll-Inc can handle the pre-qualification of Business Opportunity Leads. This can be accomplished by gaining information from the leads about what their needs and goals may be. All of the leads are followed up with and examined carefully to ensure that they are suitable Business Opportunity Leads and that they will be able to provide the level of success or results that are desired.
Sales leads are generated on the basis of demographic criteria such as FICO score (United States), income, age, household income, psychographic, etc. These leads are resold to multiple advertisers. Sales leads are typically followed up through phone calls by the sales force. Sales leads are commonly found in the mortgage, insurance and finance industries.