What I understand about Quality links is when a site linked to a another site where one has higher reputation.
for example if site a has a pr 5 and is more popular and site b is an e-commerce site where needs to create backlink, then site b linked to site a in order to get linked juice coming from site a. (just a reminder the site should be dofollow).
well back to your question, submitting article into free submission sites may cause of penalizing your site by google because if you submit one content in various article directory which has a very low reputation.
for example the ration of your content to the article directory is 1:5, that may cause you a duplicate contents and it will make the published content to be low quality since they've found out that there are lots of duplicate content.
hope you've understand, hey guys correct me if i am wrong about my opinion. thanks!