Here is set of videos that explains this in detail from Hardware Unboxed:
https://www.youtube.com/watch?v=6bD9EgyKYkU
https://www.youtube.com/watch?v=25x2xPh7Kvo&t=3s
https://www.youtube.com/watch?v=O1vgfyw6cj0
 

Or alternative from Gamers Nexus:
https://www.youtube.com/watch?v=D1mJMI_uaa8
https://www.youtube.com/watch?v=CL-JFh9BzH8
 

In short Intel ordered review of new Intel i9-9900K CPU for company that called Principled Technologies and allow it to publish result good 10 days before anybody else can publish own reviews because they are tied under NDA. In few days Intel published it on their own web site.

As you can see first problem here that Intel allowed publishing results way before other independent from Intel companies can publish their results. And a lot of websites simply repost this news because they