Say what you want about how bad Quora content is, Quora has the most engaging email digest I ever knew.
Every day they send me an email with some answers on topics I'm interested in, and I can't help but click on 6-8 of them from EACH email. The median CTR in any other of email digests recieved by me is zero.
I had the same interaction but one day their algorithm flubbed and sent me a question that had very obvious Avengers: Endgame spoilers in the title. I had to unsubscribe after that.
Every day they send me an email with some answers on topics I'm interested in, and I can't help but click on 6-8 of them from EACH email. The median CTR in any other of email digests recieved by me is zero.