Think of it as an assignment statement.
Destination = Source
Later (much), Dec introduced the Dec Command Language (DCL) interpreter, which converted:
copy source destination
pip destination source
But those of us that had to use more than one type of Dec system or O/S would generally go straight to the underlying utility as DCL was not always available.
(Surprisingly IIRC, RT-11 was one of those that did - I preferred RSX myself, though VMS was OK too; my first Dec O/S was TOPS-10 (sigh) those were the days!)