1. The lecture structure is poor - When you listen, you don't understand why they are explaining it and you get dazed There is almost no mention of key contents such as 'what, how, why', so you listen without even knowing English 2. The lecture drags on and you can't concentrate. - All lectures can be reduced to half the running time, and the progress is very slow and frustrating. This is the first time I've seen such a boring and uninteresting lecture in Inflearn. 3. The lecture delivery is also the worst - The voice recording is very small and the voice is slow, so it's frustrating, but what's more difficult to endure is the constant interjections such as 'uh' and 'um', which reduces the delivery and makes it uninteresting. The people who gave 5 points below are probably part-timers or at least have never taken other lectures in Inflearn.