Why do designers/manufacturers...?

Its all about money and inventory. It cost a lot of money to stock expensive "tweaky" stuff. This also leads to higher selling cost. A high volume manufacturer has to remain consistent. There are a lot of consumers, in fact most of them, that dont want to have to pay the increased high price of marked up tweaks.

On the other hand, the manufacturer is the one who knows best what tweaks will provide an improvement with thier product and which ones will ruin the design as they intended.

Bottom line...would you pay the higher cost of a product that has tweaks employed that you dont believe in? Or wait till the warranty runs out and go with what you believe in.

And lastly, who determines what is a tweak vs what is simply smart circuit design. Sometimes the cost of parts for a smart circuit design do cost more. No [one] designer/manufacturer has all the answers.

@lloydc

My stock Pass labs power cords are solid core wire, and UL approved.

I think we all know that no matter how good us manufactures design any part of a product, there will always be someone out there that believes it can be improved upon. Too many times a 'tweak' is not better, just different.

".....They would be better off designing better components that eliminate the need for tweaks such as better power supplies, rectification, regulation etc. But that would cost too much......"

11-21-14: Response34
Too many times a 'tweak' is not better, just different.

Very true, and much more common than any audiophile would care to admit.

I don't see as much advertising as I used to for techies who mod gear.

Every component is made to a price point.
Use expensive parts it has to be sold for more.
I can't remember exactly, but way back TAS stated something about upgraded parts that cost $5.00 more than a commercial product would cause the amp to be priced many times more than just the initial $5.00.

So replacing all the spec grade resistors and caps for example, with Dueland or whatever is the soup du jour won't just add their parts cost to the price of the component.It will be multiple times the cost of those upgraded parts.

The reason for this has been lost in time, because I can't remember what their rationale was.

I suppose you can buy a fistful of spec worthy bits and stockpile them in case of warranty issue.
Perhaps having to tie up your money in designer spares is just to costly in case of warranty issues.

A ten cent resistor blows on warranty and all you have to replace is another 10 cent one.

Now as far as the mod issue goes,maybe I've answered my own question.