Have you ever driven in a country that drives on the opposite side of the road from where you learned to drive? I think it's difficult to change.
After World War II until 1952, the United States occupied Japan. In the southern most island prefecture of Okinawa, the US military control continued until 1972. Because of this, cars drove on the right side of the road in Okinawa, even though cars drove on the left on Japan's main islands. Okinawa drivers continued to drive on the right even after its return to Japan. On July 30, 1978, Okinawa switched back to driving on the left.
This date is referred to as "730" by many citizens. The change was not popular with the people of Okinawa because it was the decision of the Japanese government. Thankfully, on July 30th the confusion was minimal and there were few traffic accidents. In Ishigaki, the transition began at 6 am, with 164 police officers and local volunteers guiding drivers to the left at what later became known as 730 crossing. A monument was constructed at this crossing. In 2008, the area around the monument was made into a public park to celebrate the anniversary of 730.