Revolving door is actually the softly killing of local people.
Amakudari ("descent from heaven") is the institutionalized practice where Japanese senior bureaucrats retire to high-profile positions in the private and public sectors. The practice was increasingly viewed as corrupt and a drag on unfastening the ties between private sector and state which prevent economic and political reforms.
However in Japan, the situation is extremely unique.
In Japan the revolving door is particular the origin of corruption.
I live in Kagoshima, which is located in the Japan proper.
Ainu people (indigenous people of Japan) is said to have lived in Hokkaido.
But I believe that Japanese indigenous people were cornered to the north and the south.
In the south, a lot of indigenous people used to live in Okinawa and Kagoshima.
However the Imperial clan's ethnic cleansing was so intense that nowadays few indigenous people live there.
We have strong dialects, but those words almost disappeared.
In my neighborhood, a variety of people moved in to the region.
And, social leaders are almost newcomers and they usually bully the local people.
For many years, I was wondering why this unusual and strange things occurred.
But now I understand the whole situation.
Japan has a strict family registration system.
Probably the system started in ancient times.
Nowadays the Japanese government has the detailed but extremely big data about people's blood origin.
In other words, the government knows who is connected to the emperor and who is not.
The word "amakudari" literally means "descent from heaven".
"Descent from heaven" is the diffusion of the Imperial clan, in other words.
In one or two generations, nuisance people are soon eliminated through the revolving door, job transfer, discrimination, marriage, social bullying and so on.
It is shown by the image something like this.
It is ethnic cleansing, something more powerful than violence or war.