Contradictory statement regarding single select listbox behaviour: selection may follow focus versus selection [always] follows focus

[kdunagan-od]

The statement regarding listbox selection behaviour in the combobox example contradicts the behaviour stated in the listbox pattern. The listbox example page states ~"selection may follow focus" but the combox statement states ~"selection [always] follows focus"

https://www.w3.org/WAI/ARIA/apg/patterns/combobox/

"In contrast, navigating among options in a single-select listbox immediately changes its value, and Escape does not provide an undo mechanism."

The above statement contradicts the below statement.

https://www.w3.org/WAI/ARIA/apg/patterns/listbox/

"In a single-select listbox, moving focus may optionally unselect the previously selected option and select the newly focused option. This model of selection is known as "selection follows focus". Having selection follow focus can be very helpful in some circumstances and can severely degrade accessibility in others."

Notes:
~"" is my way of denoting when I paraphrase a section.