And instead of thinking "Hey, Nice view" all you can think is:
It's even worse when you say it out loud.
"Hmmm, other than being a little exposed this would be a great OP (observation point). We could give full BDA and FCO on the entire valley from here... too bad about the nasty enfilade , that just means we'll need to keep the patrols out further... hmmm, good sight lines for the 240's and a few natural obstacles... now if we could only protect that ridgeline properly..."
Or when looking a new place to live, instead of checking out the decor, and the appliance and fixtures your first thoughts are
"Hmm, good sightlines, no viable ambush points, nice thick walls.. yeah that hallways is a perfect funnel into a kill zone... Nice E&E out of the neighborhood, easy access out of town... Yeah this is defensible, I could live here"
Feel free to add your own.