What observation can be made about the cities where Hoge and Morgan developed their signaling solutions?

Answer

Both pioneers were based in Cleveland, Ohio.

Both James Hoge and Garrett Morgan were involved in developing traffic control solutions in Cleveland, Ohio, suggesting that local traffic density there pushed these inventors toward solutions simultaneously.

What observation can be made about the cities where Hoge and Morgan developed their signaling solutions?
inventorTransportationSignalautomationtraffic light