It took me months to work out that "navigate to X" was the magic phrase to get google maps to do what you would expect in car navigation to do. The phrase that came more naturally to me was "give me directions to X", but that only gets you to the screen with the route and you still have to manually press the "start" button with your finger. And then it would randomly pick other modes of transport unless I remember to say "by car". Systems that are inherently unrecoverable like voice commands need actual documentation.