I am not sure why you think this.
Naval units must end their movement either in a hex with enemy
units (see examples A and B in the Naval Movement illustration
below), or in a hex from which friendly carrier naval units and
non-carrier units they are stacked with may participate in a battle (example C), or in a hex containing a friendly port (example D),...
It would seem not moving would be good enough to satisfy ending move in a friendly port.