One great example is [when] I went to a meeting and said I’m going to put sensors in the watch but I’m going to put them down here (he points to the underside of the Apple Watch band he’s wearing) because I can get a more accurate reading on the bottom of the wrist than I can get on the top of the wrist. They (the Industrial Design group) said very quickly that “that’s not the design trend; that’s not the fashion trend. We want to have interchangeable bands so we don’t want to have any sensors in the band.”
Then at the next meeting I would go “we can do it here (on top of the wrist) but it’s going to have to be kind of a tight band because we want really good contact between the sensors and the skin.” The answer from the design studio would be “No, that’s not how people wear watches; they wear them like really floppy on their wrist.”
That creates a set of requirements that drives you toward new engineering solutions […] Engineers left in a vacuum might say “well, that’s maybe not so important; we can get a better signal by doing it the other way so let’s do it that way.” So, left to their own devices, that would be the way the product would end up. So you have to have a really strong voice supporting the user. I think the idea of focusing on that is uniquely Apple.