I've just finished watching this amazing drama. I have lots of reasons why I love it, and a few reasons why it wasn't a 10/10 for me.

1. THE MAIN CHARACTERS
The storyline aside, the lead characters were quite unique. Park Bo Geum's character was my favorite male lead characters of all times probably! The personalities of male leads are normally quite similar to each other: they can be rich and cold hearted amazingly handsome, or the most skilled person in the field of whatever is their profession. Anyways, I love that Kim Jin Hyuk was just a normal guy, that fell for this beautiful and lonely woman in his own way.
As for Song Hye Kyo's character, I loved how it's showing a different side of a rich career woman. It's focusing more on her loneliness and hardships she had in her entire life instead of being a classic bitchy boss. Even though she had a really difficult life, her heart still remained as soft as it could be, and I love how she puts Kim Jin Hyuk before anything. She chooses him over her career that was her everything so many times without thinking about it twice. I love how bravely she is embracing her love.

2.THE STORYLINE
I think the writers did a very good job with this one. The love between the two characters start and develop very naturally. I loved the gradual development of their relationship: they went from being friends that are attracted to each other to a pre-relationship phase, then they start the relationship and in the end their love exceeds everything else. I think this part of the show was written very brilliantly

3.ACTING
I mean the show has Song Hye Kyo.. In my opinion she is one of the best actresses in Kdramas. She can deliver all the emotions with her eyes which I love. I also love love love her drunk scenes where she becomes just so funny. For me she is the star of the show for sure. Park Bo Geum is also one of the actors that I admire. He really made a great job especially towards the end of the show.

4.CHEMISTRY
This one for me is the only reason why I can't rate this show 10/10. Even though I love the characters, and I love their story which was so beautiful, I couldn't sense a very strong chemistry between SHK and PBG. It wasn't because of their acting or anything, because both of them gave brilliant performances. But it was just lacking a good chemistry I guess. Perhaps the love story of this show is better compared to the Descendants of the Sun, but I still can't get over the chemistry between Song Hye Kyo and Song Jong Gi. I mean yes they got married in real life which meant they had chemistry in real life too when they were shooting. But still on-screen chemistry can be very strong even when the couple isn't dating in real life (ex: Ji Sung and Hwang Jung Eum, Hyun Bin and Ha Ji Won, Gong Yoo and Yoon Eun Hye, Gong Hyo Jin and any korean actor ever, and the list goes on and on)

Overall, I think it's definitely a drama worth watching!