I've noticed many website landing pages which contain a fullscreen video that begins playing automatically once the respective website is loaded.
Usually a dark overlay appears over the top of the video, and white text appears on top of the overlay.
Some examples include:
I've also noticed that in most occasions, video controls are not visible/available to the users on such interfaces. Is there a reason why a user isn't given the ability to pause the video once it starts playing?
The reason to do this is basically visual. Sites looks nice, they have a "wow" factor and stands between other sites.
But...
they're horrible UX.
We have tested this for our own site. People couldn't stop looking for the controls. They even reloaded the site thinking the transfer wasn't complete. A couple persons with a mild or borderline epileptic condition were clearly annoyed and all in all, it was a big failure (sadly, I loved it, see why you have to test?).
Basically, while there might be good reasons to use video backgrounds, you're also adding an attention grabber element that can't be dismissed and you're yelling to the user "hope you love this, because you have no control over it!"
There are some other resources studying this feature, the pros and cons (warning, not all is bad, it could be good in some cases, just TEST in yoru case).
See Background Videos - Good or Bad ? , Video Backgrounds : Yay or Nay for UX? , Tips For Designing With Video Backgrounds
I guess you are talking about the background video that automatically begins playing in the background. You are not talking about the actual video that can be launched when clicking the ">"-play button.
In case above it true, my answer would be that the background video is simply a gimmick, a fancy fullscreen animated background image. It does not have the purpose to actually show you informative video. Hence, no video control buttons are available.
