Oh my.
If only the Echo recognised YOUR voice, then, as it knew it was you, would play back your music, tell you YOUR appointments, add things to YOUR shopping list, and allowed you to set YOUR reminders.
So different members of the family could use it in that way
And a passing stranger or intruder would be ignored as they did not recognise them.
How amazing would that be.
Of course that is how it SHOULD BE. But isn't....
One day perhaps. IF, Google Home was ever able to do this, OMG Amazon should start to panic.