This creates an interesting paradox.  On the one hand, many vendors feel compelled to have at hand a whitepaper that shows how their product or service has a real return on investment.  On the other, because every vendor has this kind of whitepaper, most HR practitioners are sceptical about the data.  It is as if it is now necessary to have this kind of data, and that it is the absence of this kind of data that would be noticed.

Unfortunately, the requirement that one have some data to prove the effectiveness of one's product or service has led to a lot of bad research.

In the end, the field of HR hasn't really made anywhere near as much progress as it could have because of the fact that it is difficult to discard anything because it doesn´t work.