Why do better MC cartridges cost a fortune?

Bill, if I remember right you have Lamm ML2.2 amps and Avant-Garde speakers, and you use Kubala Sosna cables. If I were you I would definitely wanted to try best Purist Audio and Echole cables. The outcome of this comparizon is unknown, it may be a better move than upgrading the cartridge. Each time, at a much lower level, I upgrade my Purist Audio cables and power cords, my $375 Goldring 1042 MM cartridge sounds better and better. The difference is not slight. Good cartridges have more potential than it may seem, the same with speakers.

@inna I might argue a $10k cartridge is a better investment than most other pieces of kit

consider you buy one and when you’ve got your 1000 hours or whatever in you retip/rebuild for $6k or get the same $4k discount off the new top of the line, many cartridge manufacturers also offer trade in for comparable cartridges from other lines

if you try the same whenever ARC upgrade their top of the line amps you’ll be out much more - the moment you plug a brand new amp or speaker in you’ve lost 20-30% of its value straight away

the one real downside of cartridges is that it’s really hard to get them reliably on the used market as they do wear so the cost of entry is high ... but once you’re on board it’s not such a problem

now if we really want to discuss the $10k burning a hole in your pocket I’d like to see you compare a $2k cartridge and a Herzan platform under your table with a $12k cartridge and no platform. I’d wager the former would outperform the latter ... 

Herzan platform? What's this?.
Yeah, I was talking about $10k cartridge replaced every 1.5-2 years without any big discounts and generous trade-in policies.
Generally speaking, I think $10k - $15k cartridges are really only for those who already did every imaginable upgrade, it is the last touch.

Herzan make active isolation platforms that eliminate subsonic interference. They really work with turntables but the cost of entry is $10k.

Unfortunately the sad truth is that at this level every last thing makes a difference so it’s hard to say what is the “last” thing to change 😁

Yeah, probably, that's why I said "generally speaking", this would be possible guidelines.
In any case, I hope that this thread will help some people avoid big and costly mistakes, including the mistakes they might never be aware of because the system will sound better and yet..