Not Just Bikes — Why I Don't Use Music in My Videos | [Nebula Plus]
Not Just Bikes — Why I Don't Use Music in My Videos | [Nebula Plus]
In short:
He cites an example of a Minecraft YouTuber called Mumbo Jumbo who had correctly licensed his intro music, until it turned out that the musician he licensed it from had sampled someone else, and Warner Chappell decided to enter that original source into the YouTube copyright database, resulting in 1,800 copyright claims that meant he had to go through and, over multiple days, cut out the intros of the videos manually.