What is Ermor doing?

[Gargoyle]

In SP game on Cradle map.

I've noticed something strange about Ermor's tactics. For example, I have cornered 4 provinces in the northeast of the map where there are three provinces belonging to Man and they all border one province belonging to Ermor.

I border only the provinces belonging to Man and all three of Man's provinces border the one Ermor province. Now the Ermor province has like 420 troops of all sorts in it and the provinces of Man have less than 100 each. Its has been many turns like that and Ermor never attacks out of that province. I have deliberately waited, hoping Ermor would attack and take some loses before I bash my armies into all 4 of theses armies.

Is there any commom reason why Ermor would leave large forces in different places around the map not attacking? I've seen a couple more that just sit there.