The tragedy of ornn
TLDR: passive is so cool but it sucks because it's on a tank and the masterwork items are boring, ornns real strengths are his CC and debuff, which are gold agnostic and reliant on teammates to matter, ornn is not self reliant
Ornn, the promised "self reliant" vanguard is a blacksmith forge god, burly and gruff, he breathes fire and cracks people over the head with his hammer and smaller hammer, he also has a mechanic entirely unique- to buy items outside of base. Unfortunately this passive is almost completely useless on him.
To make up for the fact that ornn can cash in on gold without losing the xp to back to base, ornn had completely trash base stats to ensure he HAS to back anyways, either because he can't itemize mana regen efficiently or his opponents straight up overpower him. This has been resolved somewhat with hotfix buffs but it's not his biggest issue with this passive
In addition to this passive being on a tank- a class thats meant to focus on the 5v5 and look passed laning phase, ornns scaling is all over the place. Ad, ap, and hp scalings stop him from ever benefiting from an item spike the way other top laners do, he can't do anything with his gold aside from build tank and continue to overlook laning phase
So riot made a passive that is perfect for aggressive laning and snowballing leads on your own and then did everything in their power to make that passive meaningless
Also there's the masterwork items- which seem to be ornns most beloved contribution to his team, something you should not ever buy until 6 items as their horribly gold inefficient, and when everyone's full build, an extra 30 ad or 10 armor isn't going to make a difference.
The tragedy or Ornn isn't that he's badly designed or weak, by design he's pretty fair, his numbers are always adjustable, and I don't think ornn is weak right now, I've seen some ornns do disgusting things. The tragedy or ornn is that riot made a champion that has a super powerful and unique space in the game, and watered it down so much that his presence became almost entirely inconsequential
You don't pick ornn to utilise his passive or to give your team masterwork items, you pick ornn because you need another tank to layer CC with, and that doesn't seem very self reliant to me