Man Is Charged With Killing His Father After Posting Grisly YouTube Video - The New York Times:

YouTube videos are reviewed by a combination of humans and machines, according to the company. It’s unclear, however, how such a graphic video could stay online for five hours before being taken down, and a YouTube spokeswoman did not answer questions about why it took that long for the video to be removed.

That combination leans heavily on machines is my guess. Also, these articles rarely identify which platform the person was radicalized. Why?