It was a wonderful 4 weeks. I think books are something that should always be read little by little and absorbed gradually, and this kind of challenge seems to have created that opportunity. Thank you.

When I signed up for the paid challenge course, it was a bit disappointing that there weren't any additional videos or materials included. However, I think the good thing about the challenge format was that it motivated me to make an effort to watch it bit by bit during my busy days. The book content seems great because it has many usage tips and useful tricks that I had been missing. Thank you for publishing such a good book!

I had high expectations for the challenge-exclusive KakaoTalk chat room. I was expecting a community space where I could communicate with fellow students and receive motivation, but in reality, it's mainly operated with one-way announcements from administrators, which is disappointing. It was difficult to feel the difference from individual notification messages, and I think it would be better if there were communication channels that allow interaction between students.