The perfect example to this is the New Mail bug that occurs when you equip a new monarchy ship.
Like... how does that even happen. What about that one piece of inventory sets off a flag for a totally separate system.
It looks like any object/inventory piece/etc in Destiny can set flags or alter other things as long as you're holding them. Like using telemetry affects weapons and stuff, or having a certain item in the inventory lets you open a door, or changes the appearance of your Guardian's biped. It could be that the ship is basically awarding something 'empty' to your mail slot. You go check your mail, nothing's there, and once you go to orbit the ship's scripts fire again and add to the mail slot's queue.
So, I'll use that as an example of bug triage. Is it a bug? Yeah. Is a
critical bug? Nope. It doesn't cause the player to soflock, crash, or does anything else to them that's bad. So they know the bug is there, but more important bugs take priority, or might be awaiting a global fix that will fix that issue and prevent it from happening again. So the bug will persist through multiple patches because more important bugs and features get in there first.
And it's really hard to communicate to players that a bug is low priority to you codewise because it sounds like you're saying their concern is unimportant, when it's not, but if you stopped the whole code team for low priority bugs games of this size would be unwieldable.
They mentioned in the stream that the Raid and Candy ghosts are now viewable in your inventory, so that's another example of a bug and triage levels. Did it suck you couldn't inspect them? Yeah, it did. Did it make the game unplayable or cause crashes? No, so it got assigned low priority or had to wait for some other backend fix.
One thing for sure has changed for Bungie since Destiny launch, though. Back in the Halo days and the launch of Destiny they'd always wait for the long term global fix, because they were used to the "nice n' clean" patch deployments. Since Taken King onwards, they've been willing to do the "ugly fix" first to fix critical bugs, like the infinite nightbow super glitch and just turning off the node, to hold off to the clean, complete fix and re-enabling the node.
And this is how every game's development is done these days.