If two scopes made by the same company have a 3X magnification range and another goes 5X are there any compromises or negatives you get when you go from a 3 x 9 to say a 2 x 10 ?

Also if a scope has a constant eye relief from say 2x all the way up to 10X vs scopes that eye relief gets shorter as you dial up the magnification is it a superior design or does it also come with a compromise or negative?

My 2.5x-25x March is extraordinary. I think price matters in this area.

I guess I was under the impression that there was no free lunch in optics even with a fat wallet.

That's just it. The need for the fat wallet means the lunch wasn't free. More complicated designs that achieve better results cost more.

and you give up nothing to have this? eye box, eye relief, weight, durability, light transmission..... I find that hard to believe money can buy perfection without some trade offs but that's why I'm asking.

You'll always give up something, it's just that more money may help you give up less. I don't dabble in the really expensive stuff so I can't comment directly on those.

Trade off is cost , You can give up on performance to save money. Don't see whats so complicated about that.

So if I buy a Ferrari for the performance I give up nothing in gas milage, reliability or room for the kids? yeah nothing complicated about that

weight has to be a factor no? 3x power vs 5x power should mean more lenses? More lenses would mean more weight.

Everything in life is a concession.

I thought we were talking scopes not Ferdes and Chebbies.

More lenses would also imply less light transmission all things being equal, no?

More lenses means less light transmission. Increased magnification and more compact design means more critical eye relief/eye box as well as more eclipsing at the extremes of the erector travel range, etc. Optical design certainly involves tradeoffs, but throwing money at the design can help mitigate some of the downsides inherent in the tradeoffs.

Larger magnification range means ‘more money’ all else being equal. As others have stated, large piles of money can cut some of the differences such as light gathering, weight to a point, etc on the scopes with broader magnificent extremes.

I agree with all of this. I will also clarify that I am certainly not a long range shooter.
I avoided illuminated reticles, definitely subscribed to less lenses the better, nothing over 4 times zoom, and 1st focal plane reticles for many years.
I think it all had merit to my eyes, at least in earlier production.

But, I now have scopes with illumination. Pretty much forced on me due to very limited choices otherwise. I have scopes with 5x and 6x zoom, and now a 8x. They could have stopped at the 5x for my use. I have some 2nd focal plane reticles that are as good or better than some of my 1st focal plane in low light.

Perhaps my eyes but I have an extremely hard time saying I lost any noticeable optical quality in low light, with the scopes that I have. These are mid-upper to upper end optics.
The eye box, I think this has improved also. Or I have adapted and don’t really notice it.
It also appears, that at least some of the manufacturers have usable low light illumination without spending 2k on a scope.

The more-zoom-is-better, and the illumination was pretty much forced on me by limited selection otherwise.
I still like my 1.1-4x24’s, 1.5-6x42’s, and 2.5-10x42’s with very usable and simple 1st focal plane reticles.

Amen.