HR Analytics constrained by small, inexperienced dedicated analytics teams that fail to change people effectiveness or HR effectiveness.
Another factor is the inability of HR to access and analyse unstructured data e.g. free-form text in exit interviews and performance reviews.
I examined this in my own article similarly named "HR Analytics an Oxymoron?"
If you are in HR follow the link to the research "Still under construction: The State of HR Analytics".
There are three primary findings: Big Promise; Small Reality Essentially, there’s lots of talk and very little action. “…most organizations are using the same tools that existed years ago to produce the same analyses companies have always produced.” Backstabbing Data “It turns out that the data is dirty – inconsistent, scattered, unreliable and sometimes just plain inaccurate.” Lean, Green and Unloved Surprisingly, the HR data analytics push doesn’t seem to be helping: “more companies said their people analytics team hinders their analytics work than helps it.”