There is a lot more to it than that ..Ive been told that really the only time your gonna notice the difference between the cheaper scopes is when your shooting long distances. After 300mtrs or so the cheaper scopes start to loose there clarity where as the more pricey scopes will still be very clear
The differences in broad daylight can be harder to pick but even then you can see the difference. The brightness and clarity issues are highlighted greatly at dawn and dusk, in fact in any low light situation. In these low light periods there is just a huge gulf between cheapies and quality glass.
Other factors include build quality ie made to better tolerances, repeatability of adjustments and tracking ability.
Then you get the things like reticle choice and warranty levels not all warranties are equal (Vortex & Leupold for example are well ahead of the field here with lifetime transferable warranties)
The one thing I would stress to anyone starting out or just upgrading is buy good optics .. they last a lifetime with minimal maintenance and will serve on many rifles. If need be buy QR mounts Warne and Leupold make good ones, 2 sets of rings and swap one good scope between rifles if you have to for a while.
I have owned Schmidt & Bender, Swarovski, Leupold, Kahles, Weaver and Nightforce among others and have sold most at times past ... I regret every single sale. The Schmidt & Bender was the best scope I ever owned or looked through I still cry at night about that one.
Any money spent on a low quality scope is money wasted in my book as you will only sell it later and no you wont make your money back.
cheers
Rinso
i love my Meopta's 
but they where the models before the"vary ex" types came out