It sounds like you think they rolled a die for every design decision that went into creating the iPod and it happened to turn out well. I would agree that there are many factors outside your control and subject to luck for a company in a situation like that, but how you choose to design and market your products aren't among them. Apple back then wasn't Samsung, they didn't just make one of everything, in as many different models as they could, and see what happened in the market. They had very limited resources and had to be extremely judicious and thoughtful about how they used them. They're not in that position now, but the disipline they learned through those years has stayed with them.
I think they were just betting the whole company. If you're betting the whole company on a single revolutionary product, you better make that product as awesome as you can possibly manage.
I imagine with each design decision they asked just two questions "will it make the product more awesome" and "can we afford it".
I wonder if stock holders knew Apple was risking that much on a project that wasn't even a computer.
