Youtube used to be better before at video playback, not as good as VLC but much better than what it is today. I think they have to deliberately hamper the user experience in order to save bandwidth, just imagine how much bandwidth youtube must cost with the amounts of users they have. Even their native android app isn't exactly the greatest which makes the web vs native comparison a bit easier.
Examples of this hampering is that they only stream 20sec ahead instead of the whole clip in one shot. There are many other annoyances like this, like not giving you the HD version even though it says the video is HD and you've selected HD, or when it re-streams the movie when you switch from windowed to fullscreen, probably because the windowed version was too low quality.
Examples of this hampering is that they only stream 20sec ahead instead of the whole clip in one shot. There are many other annoyances like this, like not giving you the HD version even though it says the video is HD and you've selected HD, or when it re-streams the movie when you switch from windowed to fullscreen, probably because the windowed version was too low quality.