[wiseleo]

They did a very good job attracting core early contributors who wrote unique great content and then it snowballed. Reading answers posted by the top 10 contributors is just fun. All content is SEO-friendly. Much of it is authoritative and Google loves authoritative content. There is a setting to make my content appear as anonymous to search engines, but many of us associate our names with our content.

Most of Quora's content is evergreen. They improved question merging recently and that resulted in a high concentration of high quality answers to popular questions. Quora's management calls them canonical questions. The ask2answer flow also improved. You can now find people who can answer your questions. That feature was previously under-developed and didn't work very well.

Quora's top contributors enjoy the virtuous cycle. We write answers and people upvote them, which introduces other readers to us. Our audiences are massive. I only have about 250,000 views per month and about 5500 followers, but some other writers have several million per month and more than 20,000 followers.

Quora will collapse answers that are highly upvoted but incorrect. This helps with site quality and likely pleases Google.

I am one of about 800 Quora's Top Writers ( http://quora.com/Leonid-S.-Knyshov ) if you have any specific questions.

[hkmurakami]

A lot of what you've listed have been true for a long time though. It wouldn't explain a sudden increase in Google search rankings.

[Houshalter]

The last time I checked quora put up a big "create an account to read this website", which seems to be gone now.

[randycupertino]

> "All content is SEO-friendly."

I think that's the crux of it. When I'm feeling lazy and google a specific question, their results pop up first because someone has most likely asked the same exact question verbatim on Quora before.

It's also really easy to fall down a Quora rabbit hole with the "associated questions" on the right side. I was watching a Star Wars marathon the other day following The Force Awakens and at one point had like 450 tabs open of associated Star Wars quora questions. Eventually I realized I could never catch up with 30+ years of nerd speculation and analysis and just simply didn't have time to read it all so I closed everything without reading them all! But I wanted to!!