Surely even a drama has to be half believable? The main plot is spread over a 5 year period but the children do not age at all. If they were in their 20s OK , but a sweet 10 year old is going to change into an unruly teenager in 5 years! Very poor thinking from the script writers and producers.
Other annoying things -sometimes visitors in hospitals have to wear scrubs - sometimes just walk in unannounced. Sometimes people have to ring a doorbell for access to the house, other times they just walk in.
Do Korean men really manhandle their women so badly? Do Korean rich really trample all over poor people , beat their subordinates with impunity, hire thugs to abduct folks and throw things around? It would have been better without all those tantrums and screaming. I still watched it though - was it to see if it would get any better?