Tempering is a system that has a significant chance of failure built into the system. The chance of failure is far beyond any other system we have in the game.
And that makes it a feels-bad system more often than a feels-good system.
While enchanting is the same kind of system, at least it is up to the player to decide when to give up, not a hard limit on the number of tries.
Also, item enhancement starts with the drop and only ends when masterworked. When a good item drops, that is already the “success”. So bricking that item in tempering becomes a “fail after succeeding” event, which feels bad.
I think ultimately, the problem is that this is an added-on system. We are already used to an item being good when it drops as a good item. Tempering now adds a chance to trash that item afterwards, so it can feel like the limit on tempering attempts feels like the system was put in to “take something away from us”.