This seems to be increasing habit with habit-less nuns (pun intended). Maybe they have the same view as Eve who didn't think being made in the 'image and likeness' of God was good enough. Eve wanted to be God.
Maybe with the 'People-is-God' attitude today, these nuns do not accept a 'consecration' performed by some 'apple eating-Jesus-acting' man.
You did not read that in Genesis, or anywhere else in the bible. It was Luzifer who wanted to be God and not Eve