The subject of the lecture itself is very good, but on the contrary, the lecture as a whole feels very unrefined. The specific details are as follows: - The lecture lacks unity as it goes from the first to the last lecture. You will think, why didn't you do it this way before? - It is a raw lecture with no editing at all. There are quite a few places where the speaker stutters or says "uh" or where the audio is blank for more than 5 seconds. When the audio is blank, you check to see if the network is disconnected, which distracts you from concentrating. - In particular, in the Meta System Design section, there is a constant buzzing sound throughout the lecture, and the instructor's voice sounds a little distorted. At least the Meta section should be re-uploaded. - Also, as a minor point, you can sometimes hear Bluetooth connection sounds during the lecture.