Hi, I'm Joe. I've been playing for exactly the amount of time as Jim. Jim got lucky with forging and legendary rolls, beating my item level by 20. Jim gets to do Mythic+ dungeons I can't, simply due to better RNG. The issue is further compounded as the content he can now do offers even more of a gear advantage, which gives him access to even higher levels of content than me, both in organised and pick up groups. Since item level is officially accepted as a measure of progression and ability, RNG has dictated that Jim now performs better than me.
I've invested the exact same time as him, played just as well as him and paid the exact same subscription fee, but due to an invisible dice roll that offers wildly different results, he's progressed further.
This is bad design.
I have mixed feelings about the amount of extra stuff you can get on gear. It makes the game feel like an even more endless gear treadmill.
Week 1: BIS trinket drops, sweet!
Week 2: BIS trinket drops with a socket, sweet!
Week 3: BIS trinket drops Titanforged +20 ilvls, no socket.
Week 4: BIS trinket drops Titanforge with a socket, and a tertiary stat.
Am I crazy for wanting to know exactly what I am getting?
This boss drops a trinket that has and will always be this item level, have these exact stats and a socket. Or he drops this helmet that that will always be this item level, have these stats, and no socket.
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To the other persons point about starting your own group: It's the fact that two people who were getting the 'same' gear but one of them got lucky with the extra stats and such that you can get on them.