See the full article for four primary reasons wearables haven't gained traction; also see Stop Counting 10,000 Steps; Check Your Personal Activity Intelligence (WSJ) and Mossberg: Smartwatches Need to Get Smarter (Re/code)
"There’s my old Fitbit, a fitness tracker I used for a couple of weeks, forgot to charge and never wore again. It sits next to a dusty Jawbone UP, another tracker that once told me I had walked three miles while I sat on my couch eating popcorn and watching a movie. And then there’s the Apple Watch, the much-hyped device that was supposed to usher in a new era of mobile computing.Where Wearable Technology Ends Up (Hint: Not Your Wrist) - The New York Times
Instead, these gadgets are ending up in drawers and closets as expensive reminders of how wearable gadgets are not ready for prime time — at least for the foreseeable future."