What you're asking for, to use the book analogy, is a list of
every single word used in a book. You'd have several pages worth of index listing the word "the" and every single page it's used on (probably, every single page of the book), the word "of", the word " a", etc. This is not helpful to someone who is expecting an index of
important words. An index is hand-curated to only contain words that are relevant to the subject of the book, and not so common as to be useless (e.g., listing the word "the" on every page). Similarly there are commands you shouldn't ever need to run. —
allquixotic 2 mins ago