Just talking generalities here and generally I'm matching the internals and functionality to the price.
$300 - $400 scope, eh glass is iffy but it works.
$600 - $800 scope, glass is acceptable, not complaining.
$1000 - $2000 scope, I could live with this glass for the rest of my life if need be.
$2000 - $3000, a touch better but man this glass isn't as good as I thought it would be compared to next tier down. !@#$, dang I could of had two of those $1000 scopes for that much.
The most expensive scopes money can buy - I can see the difference but man that's a fortune!
Diminishing returns.
Then there are the little quirks that it seems every brand has. CA in Kahles, TT toolless zero turrets turning by accident on barricade, weight of Razor - can be good or bad, dumb reticles, Blurris glass, the list goes on.
But keep in mind that ALL scopes, no matter the cost, can and do break. Though yes, usually the more expensive scopes break less frequent.
Also most of us own a bunch of factory and semi custom rifles that we don't want to put a $$$$ scope on.
I'm mostly sure I won't be spending the big money on scopes again if I can get all the features I want in a $$$ scope.
No I'm not pretending a Ares BTR Gen2 is a ZCO, on the other hand it gets the job done at 98% success. If I was rich, yeah sure, why not.
I'll stay with the old hottness, which used to be the PM2, all payed for, and mounted on the expensive rifles.
Eh, these Gen2 Ares BTR's are "just" what I need.