I've said this before in a few threads; In my honest opinion Bungie seemed like they didn't really want to continue the series after Halo-3. To gain their freedom from Microsoft they had to make two more Halo games; ODST and Reach. ODST was a pleasant surprise, it was meant to be a 4 hour DLC and turned into a full game when the team working on it went overboard. Now Reach on the other hand genuinely seems like a game, at least from a story telling perspective Bungie didn't want to make. Bungie essentially had three options in terms of story telling in making what would become Reach. Make Halo-4;in a vidoc they said they thought about it for about five minutes and shot the idea down since they wouldn't be able to continue the story themselves. Make a side story, like ODST, except on a bigger scale. Then lastly there was the option they went with, make a prequel. Now, we all know Halo already had a official canonical prequel Eric Nylund's the Fall of Reach novel. Despite not initially being commissioned by Bungie, the story stuck to the series bible and the writers at Bungie liked the story enough that they intergrated story elements, characters and tech from the book into Halo-2(Super MACs), lots of references and quotes from Cortana in Halo-3(Halsey's conversations with John and certain UNSC ships being rated for atmosphere(Pillar of Autumn). With all that in mind, why not just make a game based on the Fall of Reach with a slightly expanded story? Bungie has stated several times they are not in the business in making remakes or retelling a story in their universe that's been told in another medium, so Reach had to have a new plot. So, they developed new characters and a new story to bridge the gap from Reach to CE, even if it broke some pre-established story canon. The ironic thing about Reach's plot and the big breaks in story canon is that so much of the plot, settings and characters stem from the expanded canon it disregards; Halsey and the Spartan-3s to name a few examples. Considering how much effort Bungie put into all the details, story elements and direct references to the expanded canon in the games, it seems odd they'd collectively say screw it when it came to Reach's plot. But there is something some people on the forum haven't considered; the folks a Bungie have said on several occasions they really wanted Halo-3 to be the end of the series, at least for a while. They knew the series wasn't really thier's anymore and more than likely knew about some of the story changes MS had in mind for continuing the series. I wouldn't be surprised if some of Bungie's writers weren't happy about 343 fundamentally changing a lot of the main plots of the series; the Human-Forerunner connection, along with bringing back characters from the dead like Spark, despite him being lasered into a million pieces and the bewildering number of spartan-2s that either should be dead or shouldn't exist period(Spartan-Black and all the other Spartans that supposedly died in augmentation). If I were in their shoes, I probably wouldn't have put much effort into the story either since MS probably would have changed it eventually to better suit their own story lines. They were also probably desperate to finally make a new game with new characters and a new story after more than a decade of making Halo. Reach with all it's flaws was the cost of that freedom. No this is just an opinion. I could be completely wrong, but if what I said is right then it kind of explains why Reach was such a half hearted effort from a studio the normally does anything but.