When you step back and look at it, it's weird. 19 of the books put out in the first wave have been canceled, and of ALL the 69 titles since the reboot (including ones that haven't come out yet) exactly 1/3 of them failed. I think a lot of that is because DC has been pushing stuff people don't want, like Firestorm, Red Lanterns, or Resurrection Man; whereas other comics seemed interesting at first, but don't pan out, like JLI, Static, or Team 7. I think the majority of the blame needs to be put on the editorial teams. If there was more planning on the front end, we wouldn't have to settle for bad books, that DC knows will be bad, doesn't promote, and then cancels. It's like some things are only published so they can say they're not running a deficit, lose 4 books, need at least 4 books to replace them.
I'm calling it now that Green Team will be mediocre at best, and The Movement will be terrible, as will Vibe. Constantine could be really great, if the creative team takes its cues from his old Vertigo series.
Red Lanterns hasn't been cancelled no matter how much you hope or wish it is. As for the new wave books that got cancelled, I doubt that DC purposefully puts out bad books. They definitely don't promote their lower tiered books but they hope to be surprised by it's success. They want another Swamp Thing/Animal Man success story. Their character catalog is so big that they'll never run out of books to replace the ones they cancel.
I do agree that the original new52 was a rushed mess, but by now they should have more concrete plans on where to take this new universe. Not all the books that have been cancelled have been bad. Sometimes good books don't find a big enough audience.