This GovExec piece discusses the problem of job classification in the government, using the term "grade creep", which brings back old memories. Back in the late 1970's the Personnel Management Division (now HR) did a classification review of the branch I was heading (we had directives and records management responsibilities). They down graded the analyst positions.
As the dust was settling, I was offered a job on the program side of ASCS, which allowed me to maintain my GS-13 grade.
The classification standards for management analysts at the time were, IMHO, developed based on work in the New Deal days. To get the highest grade levels you had to be creating new organizations and new processes. I could see the logic of that. The impact of the people involved in creating the AAA back in the 1930's was more impactful than the work of people making ASCS work reasonably well in the 1970's. That didn't mean I liked the results.
Note: the GovExec piece argues for using computer algorithms for job classification--I have strong doubts about that.