Plenty of federal hires are for no good public purpose or reason. And plenty of "good" positions are filled by "bad" people, and the system does NOT tend to correct this sort of error.
I was thinking along the lines of either the appointer being unqualified to have made the appointment or the appointee having falsified credentialing.
Like when first Co I worked at found out a VP did not have claimed degrees/experience and was booking bid/proposal $ as revenue for the purpose of obtaining financing...