The explanation of difficult concepts based on practical workflows was a huge help in my understanding. In particular, I gained a perspective that allows me to think critically about why data systems are designed in certain ways, and this lecture has enabled me to consider system structures from various angles when working on projects.

1. This isn't material created to teach someone; it feels more like a knowledge-sharing study group or a presentation. It's not detailed at all, and the lecture proceeds at a level where the instructor is basically just reading off the PPT slides. - They explain something, suddenly ask "Any questions?", and then a Q&A session follows. Anyone can see this is just a recorded video study session, right? 2. When explaining complex flows, there is no cursor or pointer, so it's often confusing to know which part is being explained. 3. Perhaps because it's a recording of a video conference???, the image quality is poor and the text is blurry. 4. Perhaps because it's a recording of a video conference???, the audio quality is not good. 5. This is a lecture on a Korean platform, yet the materials are prepared in English??? I don't understand. The lecture description says it's "advantageous for future overseas employment"????? It's not like I'm going to use these exact materials as-is. I suspect they just wanted to reuse the video materials they already had. That's just my guess. [Actual outcomes regarding the expected effects after taking the course] 1. Software System Design Principles: You will understand core design principles that ensure system stability and scalability. 2. Performance Optimization Techniques: You will understand various optimization techniques and strategies to improve system performance. 3. Building Stable and Scalable Systems: You can build systems that are scalable according to changing requirements. -> I believe it is absolutely impossible to understand these through this lecture alone. It's only possible if you personally research and study the technologies required for each system in detail. 4. Application of Real-world Cases: You will cultivate the practical ability to apply learned theories to actual projects through various real-world cases. -> I don't think even a developer with over 10 years of experience could cultivate the practical ability to apply this to real projects just by watching this lecture. The PPT is just at the level of reading through materials, so there are too many things you have to look up one by one for an accurate understanding. 5. Team Leading and Decision Making: You can develop the capacity to lead a team as a technical leader and make important technical decisions. -> Becoming capable of team leading and decision-making just by watching this lecture? I think that's absolutely impossible. This lecture lacks hands-on practice, and since the content is just reading through a PPT, there are too many things you have to look up individually to understand properly. Am I the only one who finds this strange? While looking through the reviews, I saw a reply saying: "The initial curriculum of the lecture stated it referenced Alex Xu's System Design Interview book, so why complain about the lecture following it exactly?" Honestly, it's a bit funny. Shouldn't they have written that they would lecture exactly from that book and only add necessary parts, rather than just saying it was "referenced"? I've never read that book, so that's not my complaint. Honestly, what do I care? -- This lecture costs 123,000 KRW, but I think around 30,000 KRW would be appropriate. But even at 30,000 KRW, I'd rather recommend just buying the book. Developers are having a hard time these days because jobs have decreased significantly, and seeing such a low-quality lecture makes me angry. In the past, when the supply of developers fell far short of demand, 100,000 KRW honestly wasn't a big deal, but that's not the case anymore. There are tons of people who can't even find work. They probably watched this lecture hoping to increase their competitiveness even a little bit, and it breaks my heart to think they might have felt as empty as I did after seeing this lecture that lacks any real substance.

I can't hear your voice very well.

Several instructors give lectures, and to be honest, some make things very easy to understand while others only make sense halfway. I think that's because their teaching styles are different. So, my solution is to take the lecture materials from the instructors I don't understand, update them using an LLM, and input the parts I didn't grasp as prompts. Asking it to explain with visualizations seems to be very helpful.