Destiny expansion The Dark Below introduces changes to how raid gear is obtained and upgraded, so you won't end up getting no loot over and over.
Destiny is great and I love it, but the Vault of Glass raid system was pretty rubbish. My housemate ran dozens of raids before he ever got an equipment drop, leaving him stuck in level 28 limbo with six chatterwhites, 98 ascendent shards, and a pop gun. Meanwhile, another of our clan members received so much loot so quickly that he lost all interest in playing the game and prefers talking about how dull it is now he's got two level 30 characters and a vault full of maxed-out weapons.
According to a GameInformer preview of The Dark Below, that's all about to change. Bungie staff are equally fed up with crappy raid loot drops, apparently, and have adjusted the drop system accordingly.
In the Crota's End raid, Destiny will do a better job of tracking what loot you've received, and how long it's been since you got a proper reward like a decent weapon or piece of armour, as opposed to upgrade materials. Bungie is said to have "strongly implied" a "more consistent reward experience" in Crota's End than in the Vault of Glass.
Additionally, the raid will drop a new kind of upgrade material - Radiant shards and energy. These new materials will be used to upgrade Raid gear only. The thinking behind it is to prevent players hoarding their Ascendent materials for Raid gear rather than spending it on Legendaries and Exotics that offer immediate, if smaller, upgrades.
It's not clear if either or both of these changes will be applied retroactively to the Vault of Glass, but there is one other major equipment change coming with The Dark Below that will apply to everything and everyone, whether they buy the add-on or not: buying Legendary gear from vendors now requires a Commendation. These are obtained when you gain reputation ranks.
The Dark Below drops on December 9.