I think this is mainly because of the abundance of information available on social media and web. People are getting most of their answers from other resources that are feasible. Also, Quora lacks in inter community engagement. Most of the users are not posting stuff or engaging with each other personally. This shortage of community interactions and creator economy, the churn in total active users in arising!

I have personally found that the answers are tilted toward self-advertising.

The top answer is usually good, but the 2nd and 3rd answers are “check out my product”. I get it, but it has been off-putting for me.

In general, I still think it’s a good service. It just needs to be cleaned up a bit.

Same reasons as Yahoo Answers I guess (what siddheshL wrote)

I was a prominent Top Writer and I can give my impression of the consensus of other Top Writers.

It was known all along that Quora was losing a ton of money. They said prominently that their goal was to establish market dominance and then figure out how to monetize it. Several different approaches were tried and discarded, before eventually settling on the standard "put ads in front of eyeballs" approach.

In a lot of ways it just followed the pattern of so many sites (and before that, message boards). Everybody is cheerful at the beginning, feeling lots of elbow room. Then it starts to feel more crowded: topics are discussed to death, resentments build, trolls and spammers move in, etc. Moderation wanted to keep a light hand to maximize the audience, but they would still be accused on all sides of censorship and partisanship.

Really, the question is why it was ever more than yet another social media site. The answer is that they spent a ton of money, and pulled a lot of strings to attract celebrities. Its big early wins were Silicon Valley luminaries, which attracted enormous followings of people who hoped to become Silicon Valley-style rich off of that.

I could point to a ton of missteps that irked its most prominent people, but in a way that's a red herring. What the site wants is to put a lot of ads in front of users, and for all I know it's achieving that. The power users like to think that they're an attraction of the site and that once we leave, others will too. Maybe that's right; I don't know.

I'd definitely put its Partners Program as a point they could not walk back from. They paid people to post tens of thousands of questions, with the goal of attracting people to answer. I assume it worked, since they kept it despite numerous complaints. It's antithetical to what the best writers wanted, and if it worked it was only because those writers had given it a high SEO rating.

I personally gave up after seeing a persistent anonymous troll one too many times. Anonymity on Quora bypassed all of the tools that allowed individual users to block people, despite Quora's "real names" policy, and made it impossible to track people who misbehaved. Since then they've abandoned the "real names" policy (which they never enforced anyway), and if that's a prelude to eliminating its superpowered anonymity, that might make the site more pleasant to use.

Even so I think it's inevitable that a Q&A site will flounder on the fact that Q&A fits a narrow slot between "easily googleable" and "impossible to answer". Sites follow a cycle of "how much fun to re-answer basic questions of quantum physics and philosophy" to "the site used to be better before everybody else got here". Quora just had a higher peak, mostly because it spent money to get there.