Wasn't that for poor duplicate content though? I should maybe have put in "quality content".
Its not duplicate content - that would generally be another issue altogether.
Its thin/low value content. Either no real content on the page, or obviously bad quality (with Google likely measuring that from incoming links/user metrics).
The big voucher sites were a good example. In the past most of them just templated up their site so that even if they didn't have vouchers for a store, what was basically just a page of ads with no real content was still created (and ranked).
It'd end up with crap user metrics and/or no back links. (Or you'd force back links to it and cause a whole other issue).
Most of these sites that weren't brands just got wiped out with the Google updates. I think now every page on every site needs a reason to exist from a user point of view. If its not useful, then its generating risk that it brings your full site down.
Adding 'as much content you can' is easy. You could create thousands of pages over the next 48 hours with a Textbroker.com account and it all posting straight into Wordpress. But its near certain to get you penalised.
Concentrate on a handful of high quality pages. You should be spending more time promoting your content than you are creating it. Unless you're a big brand - just spam up the search results with no value add pages, and it'll probably be fine.