Why Build a Roundabout?

Why did the intersection of KY 363 and KY 1006 need to be rebuilt and was a roundabout a good fit? Here is a video showing traffic backup before the roundabout was built and after. Note how far the traffic backed up at the 4 way stop intersection and note the lack of traffic backup at the constructed roundabout. Both of these videos were filmed on a Tuesday at 5 pm to give a good comparison of traffic before and after on a similar day with similar traffic during the peak hour.
Posted by London KY Roundabout - KY 363 / KY 1006 on Monday, February 22, 2016