On September 23, 1989, the Korea Times, with great subtlety and grace, reported on an emerging social problem:
It may be difficult to discern, but I think a close reading of the article may turn up a bit of disgust at the 'hobos,' 'bums,' 'vagrants,' and 'loafers' infesting the country, and gives some idea of how migrant workers would be treated in the future. Actually, once the Industrial Trainee System (ITS) systematized their entry into the country two years later, it could be said that things got worse for them, since they were forced to pay outrageous recruiting fees to come to Korea, and then had their wages controlled and kept low (with forced 'saving plan' deductions making them even lower), while being considered 'trainees' (and so not subject to labor law protections) and only allowed to stay for two years, which was not enough time to pay back the loans back home they took out to pay the recruiting fees in the first place. That system - and the fact that working illegally could pay twice as much for the same work - essentially mass-produced a colony of illegal foreign workers, who amounted to 80% of Korea's 350,000 migrant workers in 2003. On the other hand, since the ITS did allow them to enter the country in (eventually) sizable numbers, it at least meant that not every south or southeast Asian seen on the street was considered to be illegal, as may well have been the case when the above article was written.
More of the development of the ITS can be found here.