They appeal to privileged students with well-educated parents. There's also a queue system in place to these schools which have many years waiting time, further

They appeal to privileged students with well-educated parents. There's also a queue system in place to these schools which have many years waiting time, further segregating "active" parents from "inactive" parents. These students require less resources to educate and thus generate more profit. Also the students are now customers, and should ofc be made happy to give good ratings, which has caused grades to be inflated beyond the students actual results on standardized tests. Furthermore these schools generally market themselves as "international schools" with English as the primary language, making them able to use a loop hole in the law to employ cheaper non-licensed teachers from abroad.