I have a question.

The Emperor's Children have always pursued perfection in all its forms (martial, mental, strategic, táctica, etc.), so I was wondering why they (canonically) abandoned the use of armored vehicles (Except Rhinos) and tanks. How would that help them in their quest for perfection? Or is it just a feature of the board game?

I don't have much knowledge about tactical strategies or how a war works, nor have I played with miniatures, so I would like someone with more knowledge to explain it to me.