In case you've forgotten the Stack Exchange system's black sheep, Programmers.SE, it's still around and is still in need of serious direction. Even after the Great Subjective Debate of 2010, tons of questions on Programmers.SE are still low-quality and flaunt the guidelines of both the FAQ and Good Subjective, Bad Subjective.
I'd give you examples, but there are so many of them a quick visit to Programmers.SE should provide you several.
Furthermore, there's very little incentive to vote to close questions because there are more people interested in maintaining the anarchistic status quo than there are that are interested in implementing the new guidelines. Many of the questions that are closed are reopened in much less time than it took to get enough votes to close them: right now 1 out of every 3 questions that are closed are reopened.
There are other issues, like closers being cast as villains and a severe collective misunderstanding of what constitutes a good question, but I wonder if there's at least one way to make it a little easier for beta sites to shape the character of the site:
On beta Stack Exchange sites, require (significantly?) more rep to reopen a question than to close it.
This change would, at least ostensibly, still allow many users to get rid of the cruft but also require significantly more time for users to understand the nature of the site before deciding that a question should stay.
This is based on the idea that in the beta, a Stack Exchange site should be more exclusive than inclusive: as Programmers.SE has shown, allowing a site to have a lot of bad questions at the site—in hopes of sparking a critical mass of questions such that the good questions will eventually overtake the bad—is a demonstrably unsound philosophy. And while Programmers.SE is the extreme, the problem of constant off-topic questions can and has affected other sites in their beta.
Would this help? Is there another way to help mitigate the constant reopening of bad questions?