Saves on bandwidth and video size.

Is there a particular one you are having trouble with?
Are you making the video full screen? If so what is the size of your monitor?

Yes it is fullscreen but I use my laptop any other videos from YouTube it will high quality except this

It kind of depends which videos you are watching.  Many of the older videos that have not been re-recorded yet were produced at a lower resolution. So...   If you are speaking of some of the courses yes those have lower quality resolution than say the current TechHelp or FastTip videos.
Unfortunately you can't watch at a higher resolution than what it was produced at.

The other possibility is that internet connection speed could be affecting you or your service provider may not be allowing higher quality.

Older classes were produced at that resolution, which was standard at the time. Tens of thousands of people have been able to learn from them just fine for the past 20 years. I'm in the process of updating them, but it's a slow endeavor.

Understood

Thanks