Comment by felixgallo

I don't know how LG is doing it, but I suspect that they are taking the same approach for wakewords as Alexa does/did. When I worked for Alexa, it was public knowledge that we used relatively inexpensive and low power chips dedicated to wakeword detection, and those would wake up the main chips if they believed that they heard the wakeword. To my understanding, we did this because doing cloud-based wakeword detection was considered incredibly expensive and wasteful, and there are vendors with pretty decent and inexpensive wake word detection chips.

Then, when the system was more awake, it would attempt to figure out whether the wakeword was real or not (e.g. sometimes certain words and word pairs have a very similar sonic signature to 'Alexa'), and if it felt confident enough then it would begin streaming audio to the back end for significantly improved voice recognition.

Since Amazon took (and as far as I know still takes) voice privacy incredibly seriously, voice recordings and data were treated as essentially radioactive waste, deleted as soon as legally possible, and secured against even internal Alexa developer access.

I personally don't have the same level of confidence in security with LG, who seem to think they don't have as much to lose as far as customer trust goes and might as well exploit the heck out of the systems they have. I suspect that problem, which Amazon has so far pretty successfully avoided for the most part, is self-correcting over time.