They says that Stack Overflow is a community-driven web-site.
But, as a matter of fact, it is not.
There is no community at all. It's more like an imageboard, as a number of participants makes them pretty much like anonymous to each other despite of registration.
Stack Overflow is a site of passers-by.
Passers-by who want to solve their silly typo problem and passers-by who eager to share their vast knowledge in spotting silly typos. And - oh - sometimes to perform a civic duty and vote to close a question they have no idea what to answer to and thus calling it "not a real question".
So, as a funny consequence, whatever question can get
- answered
- upvoted
- downvoted
- closed
- deleted
depends not on its quality but only on the fluctuation happened to "community" at the given moment, at a pretty random rate.
It is not only quite discouraging. It makes the very idea of collecting and improving knowledge quite impossible.