A quality drama, don't give up and watch until the end to understand its quality.
Casting is also perfect, there is no doubt, Wi Ha Joon is perfect in the role he plays (I love his acting in both Little Women and The Worst of Evil) the casting and acting of everyone is perfect as if they were chosen with tweezers.. there were moments that made me seethe with rage and there were also those that made me cry with rage.
The drama is a sharp indictment and criticism against the education system in Korea, the pursuit of excellence by memorization and not by self-thinking or analyzing situations, at the same time I have a reservation that the drama is apparently boring, there is a lot of talk about grades/tests and the grading system of tests. Sometimes I found myself repeating episodes or dialogue (one must say witty) to understand things, which leads me to think that the drama mainly speaks to viewers from Korea, they can better understand the depth of the drama than a western audience, most of the filming was done almost in the dark (even the room of The principal of the college it's dark not to talk about intimate scenes and a kiss lol) which made it difficult to watch. There are a lot of silences but the silences are so necessary for the plot (really wonderful acting) I've already seen series that deal with the strict education in South Korea and the attitude of the parents to their children and teachers regarding achievements, but it was on the edge (from what I saw), this drama gave me a different perspective ...
Of course, it has many important and universal topics related to education and interpersonal communication, (relationships between students/teachers/and parents and interpersonal relationships on a romantic background and pure and supportive love)
The soundtrack of the drama is great and pleasant throughout the drama
I rated the drama 9/10 for me it was another introduction to culture and it takes time to get used to its pace and plot...
And it may be true that she is not suitable for everyone, this is my personal opinion and I would recommend giving her a chance♥