Quite a few years back I upgraded continually, from a Naim 5i through to EAR 890/864 combo, from a Dyno P75 on through to a Tron phono stage, DV10 cart to Koetsu Red, my lovely gyro to a SME 20/2, and my little Harbeth P3s to SHL5s. All the steps were an improvement to me at least. But in those days I was continually setting-up the system, moving speakers about until it all seemed perfect and so on. It was all a bit overkill looking back and though I definitely had amazing times listening to the music I was often dissatisfied with this or that.
Somewhere along the line I wisened up, and relaxed a bit. That might be because I'm at the stage now that a significant upgrade would now cost me silly money which I can't afford nor want to spend. But for whatever reason I can listen to and enjoy music much more easily without finding minor faults here or there. So, in terms of enjoying my system, I don't think it was necessarily any piece of kit that upgraded my appreciation or system, rather perhaps the exact opposite....