this one is irksome. "quite" seems to have two meanings, whose use supposedly depends on the gradability of the adjective or verb. note the disparity between just these two sources in the example of "this is quite a different problem" under the "completely" meaning in the oxford dictionary vs the "normally meaning of rather" for "quite a/an adjective noun" phrase per bbc.
if one were to tell his wife that, yes, he quite loves her, would she hear completely/totally or fairly/to a certain degree? that would put one's money where his mouth is.
incidentally, czech has its own word that quite matches "quite", docela. so if we want to avoid fuzzying this whole exercise into near uselessness by accepting anything from fairly to utterly, we do have an excuse in the availability of a parallel czech term that matches the ambiguity of the proposed english one.