What is your experience with the law of diminishing returns ?


As subjective as it might be. Personally, I have not encountered it yet.
inna
Law of diminishing returns, thats for peasants and serfs who think of price of something, how crass and crude...!

Without any reference point, this is a tower of "Babel"; it's like asking the question; "How far is it from here to Chicago". Where is here? If we don't know that, what's the point of the question.

I suggested a reference point that I know is valid, and even if you disagree, I would hope that you at least know what it is; so far this is a totally meaningless conversation.
I don't understand the question asked, so if the OP could please elaborate a bit that would help.

If the question is about the direct correlation of performance plotted against price and the point where the performance curve begins to flatten against increased price, I stay away from that transition. I neither have the funds to spend in that region nor do I feel the need to waste valuable resources to gain such self-convincing, minor, improvements.
When I first started upgrading, I could hear the difference.  However, I couldn't always tell if the upgrade was an improvement, just different.  Eventually I learned.

I hit diminishing returns when I couldn't hear a difference after an upgrade.  But there was still a  cumulative effect from multiple upgrades -- like I couldn't hear differences each time when upgrading amp, preamp, and cables, but after all three upgrades, I could hear the sound was better.

So I kept upgrading until I got to a level where my ears/brain had stopped learning and I really couldn't tell any more.