It takes some skills to speak to an audience that can't see you (not read your lips, not see your body language). And also to speak so that people with English as a foreign language can follow, i.e. not too fast, no broad accent, and no mumbling, but with an even volume. That is what they need to practise. The actual video was ok. Some parts were also a bit too fast, but on the whole, I have nothing to say against the video.

The fact that I had a very bad sound is probably my own fault, or the fault of my equipment (I'm not at home, and I had to use my laptop). Also, that the picture appeared bit by bit might be due to my connection and the fact that I'm half a world away from you. I can't remember if any of the other participants mentioned the picture, but there certainly were enough complaints about the sound.