Why don't upgrade the wires and components inside our units?

I have been upgrading what most companies ignore,out of site,out of mind 

most companies use at best average Xover parts the Xover is the. ♥️ or the 🧠 

of the speaker it most cases even with great drivers a weak link 

I look fir gems or speakers say 5+ years old and rebuild them I just spend $1500

on all the Xover parts for a beautiful pair of Dynaudio Contour 3.4LE  parts quality average like Solen and ceramic resistors ,I use top Either Mundorfs great new Ultra copper foil resistor ,or the close second Path audio from Poland  $30 each vs the $2  in your speaker,  and rewire I bought high quality Cardas wiring Occ copper 

and WBT  connectors , this$1500 spent will turn a $7 k speaker into a $15k+ With ease, a  profound improvement ,it’s Xover is  actually a bottle neck for most stock speakers .after 20 years  I have literally mega 1000s of hours in comparing and listening. Buy a custom built speaker,  Tony Gee of Humble homemade hifi capacitor test  makes great speakers for all budgets check out the capacitor test it covers 95% it pretty accurate ,

 @vanson1 In my opinion, you could not be further from the truth in your statement thet "there is much more to be gained there". And there is certainly a lot of low hanging fruit to be had to this end especially if you have some basic mechanical skills. It's not that hard. (seems like you already may know this). All my amps have direct wired DH labs silver copper AC all the way to the fuse block. I use mil spec ptfe insulated silver tinned copper inside and honor the wire gauge of the original design. My experience is with 1980's 1990's vintage high end gear and have had amazing results along with mods based on long standing consensus in the DIY community as to the efficacy. Just be forewarned, opening the cover can lead to a deep rabbit hole. @larryi I appreciate your direct experience with a certain mod, but those that mod either for themselves or for business would stop doing it or be out of business if it was not highly effective.....

Peace

I upgraded my interior wiring and speaker post on my vintage Klipsch Cornwalls, made a HUGE difference, bigger sound difference than anything else I did to  them...

Wires, unless they are corroded or burnt, do not get 'old' and do not need replacement.

Semiconductors do not need changing unless burnt.

Resistors are about the same.  Leave them alone unless burnt.

About the only thing worth changing are the capacitors, especially electrolytics.

If you have them, another type of component also worth changing are relays and mechanical switches.  Their contacts do oxidize and changing them may be a good idea.

If you have surface mount components, this whole thing becomes a difficult task.

I started with my Cornwall’s, LaScala’s ll & now ready to do my Chorus ll. All with 18g & 16g OCC silver on top & 12g OCC Copper on the bottoms. I tried both ways & seem to like my current way. Really made a substantial difference.😃