Quality content is greatest unsolved puzzle for digital marketer because there is no simple definition or guidelines for create a content which can be termed as quality content. Although you can find millions of articles written by best known digital marketing experts like Neil Patel, Rusty Brick, Darren Rowse on same topic. But problem is that each one has different views on creating quality content.
A google employee can be best person who can tell us best rules for creating content which can match with googles quality content guidelines. So a twitter user asked the same question to googles John Mueller. Question was “@JohnMu it is right that the attitude & magnitude of content is matter a lot than its latitude and longitude about google ?” . John Mueller responded that a good rule of thumb is content that your users will want to come back to even without a search engine. This answer gives some insight about how google measures content quality.
@prackashsingh A good rule of thumb is what content would you create that would encourage people to come back, even without a search engine?
— John ☆.o(≧▽≦)o.☆ (@JohnMu) April 4, 2017
It is common saying that traffic coming from organic source is most important but above answer clearly indicates that direct traffic is also have same importance. Because peoples may have bookmarked your article to read it in future. So If your post have 20-30% direct traffic that means you have written a article which is liked by visitors.