People have all sorts of motivations for learning languages and accents. Right now, I'm using this tech to work on my accent in Spanish. Honestly I would rather mumble almost unintelligibly with an decent Mexican accent than speak Spanish slowly and clearly with an American accent. There is a difficult but necessary period of learning an accent where intelligibility drops. For a while, I made a strange [ð]-like noise when learning the alveolar trill (rolled R), and it would have been more intelligible to use something like alveolar tap. But, I built up the muscle memory, and can now make the correct sound. Hearing a version of myself (rather than a different speaker) gives me a more useful target to mimic, and the distance metric gives me a useful measure of whether I'm closer or further from the target.