I am not trying to be quippy here, but why does Mozilla need a chief executive officer? as someone who's never been amongst the leadership roles of a company b

I am not trying to be quippy here, but why does Mozilla need a chief executive officer? as someone who's never been amongst the leadership roles of a company but witnessed the legal structure of plenty of such companies, I'm not sure I understand why it needs one, given what it is and what it does.