Way back in D3, I made multiple characters of every class and farmed all the best set and legendary items for each and stored them on mule characters. I was ready for any set and build to become good and start playing it. Then whenever Blizz adjusted items or sets, the changes weren’t retroactive. I had to farm new versions anyway. All my effort was wasted.
With D4 I was ruthless with my stash. I had the list of aspects I needed for my bulld and I kept nothing else. If I already had 2 of an aspect, I would only keep the 2 best. The only extra gear I have is 3 extra rings for trying different hearts. It’s been very liberating. When the season ends, everything my season character can take with him will fit in his inventory.