Even Snap's glasses are considered a failure even tho they FAR outsold Google's version. What snap got right was the privacy, they knew to make it obvious when a person was filming, otherwise it's VERY creepy. We think THAT aspect will remain (having the glasses telegraph when they are filming) WHEN this tech goes mainstream, but you're totally spot on with the "execution" concept wrt Google's handling of the product.
snap is well run, and here's something to bite into regarding that...
https://steemit.com/money/@harpooninvestor/snapchat-the-greatest-investment-in-the-stock-market-at-usd17-15