I have noticed that some of my triggs continue to show Never - No activity yet, when in fact I have tested them several times and they are working fine. Other triggs with the same structure report activity correctly.
Update: Ok, I think I have explained this. When I changed the external trigg activation method from an http connector to a button activated by Alexa/Google, it bypassed a couple of the triggs, and their functionality was being duplicated by an alternative trigg, making it appear that they should have been active.