I recommend reading the article. They focus on the loot cave, but the best info comes from the bullet points at the end. Bungie really did not understand how players would react to the game. Some terrible banter regarding RNG. Even though they put the best gear in RNG drops, they thought players would buy all of their gear. And Bungie is O.K. that some players will be unlucky and never get something like a Gjallarhorn. Players apparently don't like skill checks. I'm certainly not a fan of clean up after killing Ir Yut. Look at the slide of player activity. More time is spent in PvP than the raid. Way too much time spent in the tower. And not surprisingly, strikes are the no. 1 activity. I saw from other sources that Bungie though the average amount played would be 39 minutes a day. You can't even unlock a bubble on a weapon in 39 minutes.