Security of zwave & zigbee devices

Assuming an authorized person is home because a presence sensor is in the house is like assuming they are home because they left their keys on the nightstand or coat hook.

The default could be to assume that the authorized person is not home, unless confirmed with a PIN (2 factor authentication, of course… Something you have… Aeon Minimote or Key Fob, and something you know… PIN… Or Amazon Echo challenge / response questions!).