Gimbel writes clearly about what product development is about: we all know this, but seldom undertake the fundamental observation and inquiry it requires. He is eloquent in espousing self-examination, and suggests that it may come in a flash of fundamental insight.
We all have personal examples of "why didn't I think of that?" My own personal favorite is the cardboard coffee sleeve, for example. With high tech products like the iPOD, though, there's another aspect to the problem: the innovator has to convince someone to invest in both development and product development. That is, to make a bet.
There's a story going around that Steve Jobs tied up one year's supply of the mini disk so he could have a good runway to launch the iPOD. If you're making a bet it helps to have deep pockets and lots of guts, I guess.
It also helps to be good: I think a good hunk of the iPOD's appeal came with the interface design of the wheel menu, or whatever it's called. (On this one, I have to go on slight observation: I have a tin ear, so whether it's ten or ten thousand songs in my paw it's a non-event.)
Using the iPOD as an example, I wonder how many people it took to create the vision that became the original. I suspect there was one person who started it, but I also suspect there were a bunch of people who fleshed it out. I wonder how they kept their excitement at pay, and how they were able to keep the idea so relatively quiet. Apple is notoriously secretive and sensitive about the slightest premature--and unmanaged--disclosure. Perhaps if we could get Tracy Kidder or Po Bronson on the job we'd get a great story out of it.
Ccoming back to Gimbel's thesis, innovation does come from examination, curiousity and vision. It's hard work to take ideas to reality, though. It takes guts, awareness, and a good bit of engineering savvy to pull the development part off, and it takes equal guts, tenacity and knowledge to make it into a successful product. Perhaps these latter qualities are equally rare to the true innovation, because its seems we have far too few innovations of the quality of the Walkman, the Tivo, or the iPOD.