Why was Google Glass a commercial failure?

1. Utterly irredeemable violations of expectations of privacy.

2. Extreme hubris and entitlement.

3. Robert Scoble.

https://cdn.vox-cdn.com/thumbor/00wh-HifgXHkKgsppGTDxSrkpfY=...

Was it a complete failure though? Perhaps it was a product which was too early and a solution looking for a problem.