The person giving the lecture doesn't know if what he said is right or wrong and just talks. Is it Mbyte or Kbyte? False or True? Aren't you being too sloppy? I corrected the mistakes in the video with subtitles... If you made a mistake during the lecture, should you correct it immediately, or if you realized later that you made a mistake, should you re-record it and upload it instead of just covering it up with corrected subtitles? Why is it so hard to remake a 10-minute video? Do you just put the video with the mistake in the curriculum? Especially in an educational course where the purpose is to convey accurate knowledge, isn't it important to convey the content clearly and without confusion? Thinking about the people who are spending money and time to listen, you shouldn't do that. I'm listening to the beginning of the course, and I'm wondering whether I should continue to listen to the course that was made with this kind of attitude or not.