G+ lost because Google forced G+ to every Google account. Post something to Youtube, you silently created a G+ post. Upload something to Picasa, you silently published the photo to your G+ newsfeed, etc. - quite toxic. And have they learned from their Google Buzz (G+ predecessor)? Nope, same behavior.

I have somewhat similar feeling about the upcoming Win10 launch, and in near future a lot normal user will learn the hard way why they got Win10 in exchange for the current Win7/8 license.

Simply don't outsmart your user base.