Korea because it is in a safe zone near a convergent plate boundary doesn't experience many earthquakes, only 20 a year and when they do occur they are mostly not very serious ones, usually ranging from 2 to 3 on the Richter scale. The last earthquake Korea has had was on December 17st, 2021 and it was of magnitude 3.2

The map above shows all the earthquakes that occurred in 2016 and their magnitude. There were quite a few earthquakes throughout 2016 but as you can see only a few were above a magnitude of 3. Only 9 were recorded at a magnitude of 4 to 4.9 and only 5 were recorded magnitude 5. 

To help mitigate the damages of their earthquakes Korea by land use planning and zoning regulation through the National Land plane and Utilization Act, as well as individual buildings being subjected to building laws. National laws have also been put into place that say any building higher than 3 stories must require an earthquake resistant design. Alongside this the 2001 Comprehensive Earthquake Prevention Plan of Seoul Metropolitan Government requires all existing buildings of any type to be examined. 

References:

https://web.kma.go.kr/eng/weather/earthquake/intro.jsp#:~:text=The%20average%20number%20of%20earthquake,and%20it%20occurred%20in%201980.

https://www.volcanodiscovery.com/earthquakes/south-korea/archive/2021.html

https://public.wmo.int/en/bulletin/reducing-disaster-risk-cities-%E2%80%94-republic-korea%E2%80%99s-experience

https://commons.wikimedia.org/wiki/File:Earthquake_map_in_South_Korea.svg