the word competent doesn't just mean "capable" or "having this capacity/ability", it also means "with the most superior claim to the right"

compe-ten-ce - having possession of the rightful claim to a power

i was confused for some time as i heard on bulgarian news about how various departments and persons and organizations had "competentsia" and "competentsi" (competencies) for whatever thing that was being discussed but thinking back on it recently i realised it is not just capacity or capability it is also a claim to a right to exercise the role of executor or the most superior right in regards to a matter

learning legal words is quite important, these words have big meaning to people trained in them, police, politicians and lawyers