That's what the term "copyright" means, that the work in question (musical or otherwise) belongs to someone and cannot be copied without the permission of the owner (who normally wants to be paid).
Because they were an infringement of copyright.
Downloading YouTube videos without permission is a violation of YouTube's terms of service and can lead to copyright infringement. It is recommended to use legal methods such as purchasing or renting the content from authorized sources.
It could well be. You need to check the ownership and licensing.
copyright infringement
There's probably no videos of Cars 2 (the full movie, including putting it into parts) to start with. This is due to copyright infringement.
Generally, rightsholders tend to view gameplay videos as copyright infringement.
An effect the uploader added. This is done in order to circumvent Youtube software that detects copyright infringement.. Mirroring the video in this way allows it to sneak past and be uploaded.
Yes, it is generally illegal to download YouTube videos without permission from the copyright holder, as it violates YouTube's terms of service and copyright laws.
To identify and remove a duplicate video on YouTube, you can use the "Content ID" tool provided by YouTube. This tool helps you find and manage duplicate videos by comparing the audio and visual content of videos on the platform. If you find a duplicate video, you can request to have it removed by submitting a copyright infringement claim to YouTube.
Some music videos are removed due to the copyright owner claiming the video as their property and demanding the YouTube user to take down the video. Most music videos on YouTube are user-uploaded and not all of those videos have permission from the copyright holders to be uploaded and used on YouTube, which results in copyright complaints and videos getting removed.
I think that the only videos on youtube that are copyrighted are like the Vevo videos, or like the Videos uploaded by the band themselves.
With Content Identification, a tool they use that scans new videos against a database of copyrighted content submitted using a form at http://www.youtube.com/t/content_management