Middle age is when many managers experience career plateau. The career plateau is the point in a career where the likelihood of additional hierarchical promotion is very low.
It could be due to many reasons, some who were stars earlier cannot keep pace with demands of higher level jobs and decide to slow down, some stay with organisation for a very long time (out of loyalty or lack of employment outside) and stagnate (dead wood) while some are simply misfits in current environment (unable to cope up with new technology/processes) and become poor performers.
To get out of this situation one needs to retrain managers, those who are unable to cope are asked to go.
Japanese handle such managers in different way. In Japanese culture, identity of person is linked to organisation he works for, so sacking him will result in loss of face for employee at home or in neighbourhood, and at the same time organisation doesn’t want to lose its reputation by sacking employee.
They use technique called Madogiwazoku. It means “window ledge tribe”. Making employee sit near window with no work except gaze out of window.
What is means in reality is that non-performers get placed somewhere in the company where they don’t get in the way, don’t get any work to do, but still receive salary. They are isolated from their co-workers/peers.
This may result in employee quitting company on his own (desirable output for company) or he may tolerate insult and continue till retirement. One extreme reaction is employee committing suicide, for some Japanese madogiwazoku means great shame, hence prefers to end their life than sit on window ledge.