Just throw out the last one. Google should just not launch new stuff. Unless they're serious about it and they're going to keep it.
The problem is that a number of users that would make a dedicated startup quite happy, doesn't interest google - "low growth or low interest" is a rather high bar for google. Google Reader was huge, just not google huge.
EDIT: Why I think this, is because I'm annoyed that all the big companies want one of what all the other big companies have - music locker/streaming service, home automation platform, tv platform, freaking VR goggles. One does it, the rest have to get one too. Then it's forgotten in a couple of years. (Helpouts was part of the Hangouts push, and now that the push is over, it's forgotten.)
They could just start spinning off (into separate companies) or open sourcing the projects they decide to no longer pursue. That would alleviate a lot of the negative PR they get from doing this stuff, I think. Also is the right thing for customers who are invested in the product.
Google should keep services running despite low growth or low interest!
Google should be all things to all people!