Pretty interesting and lengthy read on how badly Bungie ended up botching the story and Year One stuff for the game. Basically a lot of internal arguments and the need to rush the game meant the story was an afterthought and only started fixing it after getting a lot of complaints.
Also how those problems along with technical issues ended up changing their long term plans when it came to doing expansion packs vs new releases (ex. Destiny 2). Taken King was actually meant to be in the original main game before it got gutted due to those reasons.
http://www.destructoid.com/-the-stor...y-316580.phtml