You will note I said "add to my conviction" - thus meaning that this recent discussion has added to my opinion, it's not the only reason!

I agree that ESL in Asia attracts unsavory elements, I disagree that the answer is public education; SB works/worked for state schools and universities, so saying they attract a better standard is obviously untrue given the discussion here. The answer is tighter regulations on visa applications, only granting them to qualified teachers, rather than just native speakers. Private schools that only hire real teachers, as EFDL did at one point, are examples of how private schools can work. When the standard of employee slipped, so did all other standards at the school. Ergo, if unqualified tourist-teachers cannot get a visa in the first place, the ESL industry in Asia would improve drastically.