This is the space where you can define which sensors and inputs are taken into account into determination of if the routine should get triggered or not.

Once a routine is activated, an idle state will be applied. And a list of inputs is defined to be alert in your stead and trigger the reaction if/when needed.

For each room (or your whole home), you can decide which type of inputs the routine should take into account. Those can include SpaceSense, cameras and motion sensors for now.
If one of these inputs are activated for the room at the time at which you launch the routine or before, then it will be listened to. 

Note: if you activate or setup an input after the routine has been activated, it will not be taken as a source of motion detection. For example if you launch a routine, then activate SpaceSense for a room, it would be too late. You may want to stop the scenario, then activate it again in order to take SpaceSense into account.