When widening a road, why does construction seem to inevitably include a "smoothing" out of the curves on the road, essentially making it more straight?
I've seen this personally on roads where I travel, and you can even catch a glimpse on Google satellite imagery of roads that are in the widening process: Google overlays a "ghost" lane to show where the new lanes of the road will be. It's faint, but you can see an example here on a road near Flowery Branch, GA:
Is this the engineers' way of correcting previous mistakes, or a response to devleopment that's sprung up around the road since its initial construction, or safety reasons? Or something else entirely?