KakaoTalk, the most widely used messenger app in Korea, generated about 2.6 trillion won ($1.8 billion) in sales from advertisements over the past 18 months, at the expense of corporate expenditure to fortify system operations and stability, a ruling party lawmaker said. Insufficient preventative measures amplified the service outage at an SK C&C data center in Seongnam, Gyeonggi Province, Saturday, according to Rep. Kang Min-kuk of the ruling People Power Party.