>> "For a wearable to 'really' succeed it must be 1. Unobtrusive. 2. Elegantly hidden."
I disagree with point 2. If you make the wearable into something that it already worn (e.g. watch) and make it just as fashionable you can succeed. The problem is that technology is an industry with almost no fashion sense. The closest product I've seen to succeeding design wise has been the Apple Watch and even it looks a bit clunky (hopefully this will change as the technology improves).
That's an unfair assessment of tech as fashion right now. Personally, I think the Apple Watch looks ugly, but things like headphones (over-ear and Apple's prominent white in-ear) have been prominent and very popular, especially as a social/status signal. A lot of design work goes into technology.
I think we will continue to see successful tech follow that prominent path, but also the hidden one you suggest. Google Glass done right, hearing-enhancements that are barely visible, slim AR/VR goggles that are more like glasses, etc.
I disagree with point 2. If you make the wearable into something that it already worn (e.g. watch) and make it just as fashionable you can succeed. The problem is that technology is an industry with almost no fashion sense. The closest product I've seen to succeeding design wise has been the Apple Watch and even it looks a bit clunky (hopefully this will change as the technology improves).