agree with the above of course
I like my paradigm studios, but nothing about them make them objectively "better" than another brand. People like different sounds from their speakers, and that's the sound I like at it's price point, at least from the fairly large variety of speakers that I heard. Certain brands do generally produce a "better" product than others, but I wouldn't say that any of the brands you mentioned are objectively worse at a given price point.
Is that what you're asking, or are you asking what sort of variables make a given speaker "better" than another, and I'm going to use "better" as meaning a speaker with a sound most of us would favor, just make up a really extreme example in your head. Everything about a speaker changes what it sounds like, drivers, crossovers, cabinets, the room it is in, and the research and experimentation that goes into the process of integrating these and many other things to produce the sound that you hear. Some companies are charging mor for their product so they can spend more money on research and development, as well as on the components which make up the speaker. Some companies spend more money advertising their speakers, which is obviously paid for by the consumer.This is not to say more expensive is always better, we've all heard expensive speakers we have not liked, but it gives the company the opportunity to make a better speaker. Go to this link
http://www.intellexual.net/bose.html
and read what the author has to say about the build quality of the bose acoustimass systems. This article obviously has an agenda, and I am not trying to start another bose thread, but it does describe why the author finds the general quality and build of the speaker to be flawed.