Why Contact Sensor Could Not Work in Google Home?

Google home cannot trigger Routines via Sensors, like motion sensors & door/windows sensors, which has been promising for almost 2 years, Routines can only be triggered Via Voice or Time of day. If you already have some other hubs, you can connect Sensors to them but they will not show up inside Google Home.

We need to Trigger Google Routines using an Amazon Echo. Here is a video made by Home that has explained more details: