I am not a doctor but I am from this industry. Here's some insights about Korea's healthcare.
The Korean government wants to train more doctors (and nurses) because they want to improve their healthcare system (aging population).
Many Koreans hold dual-citizenships and never give up Korea's because they want to see doctors in Korea when they are old. They are that good.
Their healthcare is so good that now their government just tell their young men to be enlisted for NS by 25 years old, and before that, they can freely go anywhere in the world to work or study. They don't need any deposits or guarantor (required in the past) to counter NS evasion because there ain't few places in the world that will offer better healthcare and social welfare than Korea these days. Eg. some cities in Korea are giving US$100,000 per baby and children get free laptop/tablets every two years.
Korea has one of the best national healthcare system in the world. People wants to retire in Korea now because of their healthcare system and training a lot more doctors and having superb hospitals (some very reputable in our industry).
You go to hospital A&E in Singapore, you gotta wait 5-10 hours if you don't have heart attack. MOH "misplanned" in mid 2010s; refused to increase intake in NUS and NTU for many years after Lee Kong Chian Medical School opened. Despite population projection and two new upcoming hospitals, MOH said it was enough and refused to groom more nurses and Doctors locally (increase intake).
The backup plan was to let those disqualified from local medical schools to fund their own studies overseas, and then offer to subsidize them partially so that they will be bonded to work in our local hospital. It was an irresponsible policy, there were few takers. Few in the right mind will want to return to serve Singapore, after NUS and NTU rejects them to recruit Malaysian, China and ASEAN students.
Concurrently, focus was shifted to groom a large number of therapists in SIT and NYP for physio, occupational, radiology, so that can replace those trained overseas. Eg, up to late 2010s, all physios, podiatrists, radiologists with degrees were from overseas.
Then as our population increased by a million every decade and fallout from COVID and aging population, we have a huge shortage of nurses and doctors. MOH went on to take the shortcut and setup MOH Holdings to hire doctors and nurses from various countries.
Our media did not tell us that our country was misguided. We should be more humble and learn from others, don't always think that we have the best, and we are the best.