They can both recognize your voice. Not sure about the Echo, but the Google Home doesn't do anything even remotely sensitive unless it recognizes your voice, bu

They can both recognize your voice. Not sure about the Echo, but the Google Home doesn't do anything even remotely sensitive unless it recognizes your voice, but it will do things that don't require auth, e.g. answering questions, playing music etc. I don't know what the false reject rates are, but they're non-zero, and failing to respond to the weather because they weren't sure it was you seems like a bad trade-off for most people.