There is a phenomenon in my country. I am not judging whether it is correct or not because of my ignorance on it. My honest opinion, as per my current knowledge, is that the phenomenon is bad as whole.
The phenomenon is as follows:
A student completes either doctorate or post graduation at university or any academic institute named N. She gets appointment as assistant professor in the same institute N whenever vacancies are present. Although the percentage of such people vaires, the percentage is significant. It may be above 50% in most of the cases. It is not just happening in normal institutes but also in premier institutes.
The medium of instruction in most of the institutes is English only. This question is not about discussing advantages or disadvantages or judging this phenomenon.
The question is only about the existence of laws or rules prohibiting the happening of this phenomenon in US. Is there any such rule?
If not exists country wide, then are there any universities with existence of such rule?
I am not asking about permanent prohibition, but at least with some restriction to avoid that phenomenon.