Will people buy wearable technology? Looking back on computers, purchases were out of curiosity and it eventually became a "must have" when games began to be cracked. Some even enjoyed the long tedious entering of code to produce a "useful" program that was painfully slow when you ran it. It took three whole days to do a spell check on a five page paper.
Then there was the verbal war everywhere with the majority advising to buy a Mac when universities only used Microsoft PCs. If you wanted to further your education a Mac was useless. I believe this state of affairs is split now but most colleges still favor Microsoft.
The iPad is still not a device one uses to improve knowledge, though some still soldier on in the fruity Apple world. There isn't much doubt that an Apple product is a prestige item. All Apple devices are grossly overpriced and owners know the ordinary Joe will never afford one.
In regard to wearables they are just curiosities at the moment, much like 3D and 4K televisions. Billions were wasted on investment in these "dead ends". Watches are so old fashioned. Even before mobile phones people were leaving them at home because there were clocks everywhere. Like cuff links they have gone to the dogs. It would be different if power and battery life was comparable to mobile phones. Unfortunately, it isn't.
Wearables will remain locked to the health and fitness world. This is where a low power, short battery life product fits in with what the user wants. Google glass will eventually fade away as non-users feel threatened by them. Eventually, someone is going to get a black eye for filming without another's consent.
Another issue with wearables is the mistaken belief by manufacturers that human behavior is predictable and consistent. People are notoriously inconsistent, going off at a whim on the spur of the moment. A meeting could start with the dust mite and end up on Mars. All conversations are like this.