* Apple II had tons of competitors on the market
* Lisa/Macintosh? Xerox PARC roots
* iPod? Tons of poorly constructed devices before it
* NeXT and OS X? Obj C is not the first "C with objects" language, Mach kernel is from CMU
* iPad/Newton? Tons of prior art (the idea itself belongs to Alan Kay)
I have major problems with Apple (they aren't friendly to hackers who don't work at Apple), but the fact that people forgot the predecessors of Apple's devices is only an example of importance of execution.
If these engineers left with only vague product design ideas in their heads (e.g., use triangulation for location awareness, use an accelerometer for rotating the screen) and built their own iPhone work-alike (which is difficult work), I'd side with them as well.