https://arstechnica.com/tech-policy/2022/11/musk-ignored-twitter-staffs-warning-that-scammers-would-abuse-paid-verification/

Elon Musk ignored internal warnings from Twitter's trust and safety team when he rolled out his failed paid verification scheme, according to an article co-published by Platformer and The Verge. About a week before the November 9 launch of Musk's revamped Twitter Blue subscription, which gave users who pay $8 per month a blue checkmark even if they weren't previously verified, the trust and safety team circulated "a seven-page list of recommendations intended to help Musk avoid the most obvious and damaging consequences of his plans for Blue," the article said.

"Motivated scammers/bad actors could be willing to pay... to leverage increased amplification to achieve their ends where their upside exceeds the cost," the document said. This warning was "labeled 'P0' to denote a concern in the highest risk category," the Platformer/Verge article said.