The Newton, unfortunately, could not leverage itself using Apple's share of the desktop market. The Palm Pilot, which could sychronize with a Windows computer, proved the concept successful. Apple learned from this, and made the iPod Windows-compatible. That's a nice lever.
Now, if Apple could introduce a Newton that could synchronize with either Windows or OS X, I think it's chances would be good. It would still need to be "insanely great," of course.
Yes, the telephone is a good illustration. But keep in mind, the refinements I mentioned cover a period of time from 1876 to 1949 (original invention to the "G" series handset.
That's GLACIALLY slow.
Now compare the first commercially-available MP3 player (I forget...), the first-generation of the iPod, and now the nano. That's about, say, six years? I'd say competition is the difference there. "Ma Bell" had a so-called "natural monopoly," whereas Apple must keep making the iPod better as fast as possible if it wants to keep its lion's share of the market. As Apple hasn't shown any signs of slowing down, they're going to remain "in the catbird's seat" for some time.
[Sure, the vertically-integrated "lock 'em in" iTunes Music Store+iPod business model is a factor, but I don't think that's what's stopping folks from buying more of the other brands. Using myself as an example: I've never bought a track from the iTunes Music Store. I still buy my music on CD, and rrriiipp! Should the iTunes Music Store ever start offering higher bit rates (my preference would be Apple Lossless or WAV) for similar prices, then I'd start buying.]
The original telephone is another example of a not-yet-ready-for-primetime device that needed much refinement to become indispensable.
Alexander Graham Bell started with an original idea--changing voice into current and back again. If you think about it, what he actually invented was the microphone and the speaker. Telephony was the first obvious application, hence the name.
Mr. Bell thought his invention would be used for broadcasting, such as carrying the sound of a symphony from the concert hall to another venue. The idea for point-to-point communication came later.
Thomas Edison provided improvements to the telephone, such as the carbon-grain microphone, a dramatic improvement at the time. That microphone worked well enough to continue to be used in telephones for the better part of a century.
The "iPodification"--for lack of a better term--of the telephone, I think, was the introduction of the "candlestick" phone. No longer did one have to stand at the wall to use a phone, one could sit at a desk or on a comfortable chair and chat. The rotary dial was the next great refinement, as was the all-in-one handset to follow. Making the telephone user-friendly is one of the reasons for its ubiquity; ANYBODY could use it with minimal instruction. Sound familiar?
Even the oppressive, omnipotent, monopolistic AT&T (the Microsoft of its day) managed to continue to refine the concept. Great thought went into the "G" series handset, which can still be found on payphones today. Previous handsets looked cool, but the plain, boring "G" series handset has been in use for over 55 years now. Part of the reason for that handset's success was its flat-backed handle, which made it naturally cradle-able between one's shoulder and tilted head. Previous "E" and "F" series handsets, such as one might see in an episode of "I Love Lucy," had rounded handles, require much effort to cradle.
Sure, you can admire a refiner as much as an innovator. Many of the great inventions we know were not instantly suitable for the end-consumer; aesthetics and ergonomics are extremely important selling points.
What if Microsoft Never Existed, Part 2: A Destiny Destroyed
Apple: Bringing You the Innovations of Others Time and Time Again
Apple: Bringing You the Innovations of Others Time and Time Again
Apple: Bringing You the Innovations of Others Time and Time Again