It's shorthand for stating a dislike of Google's reputation for short term thinking around products - whenever there's a new Google launch many people's immediate reaction will be "Looks ace, but is it worthwhile investing the time and energy necessary?". That's a complaint Google should take seriously. It's how lots of people in the tech community view Google. As you say, it seems to be posted every time Google launch something.

There was a great comment by jsafi here on HN a while ago suggesting why Google are like this - https://news.ycombinator.com/item?id=19553840

It's hard to imagine a way they could change it besides stopping launching anything that doesn't have a long term plan in the company.

The reputation of google products being shutdown now preceeds anything they release. It is tarnished, and would never be repaird till they pubically announce that they intend to keep it running (which, of course, they will not).

Therefore, anybody that's not just curious, but is instead going to be invested in using any product of theirs would do well to find an alternative, and invest in finding ways to export to said alternative.

Googles' products can no longer be trusted to remain, and i urge anyone to never rely on it remaining.

A lot, it lets people know that something cherished might be suddenly ripped out from underneath them

A fair warning to people who would otherwise get excited. A reminder to people to not tie to Google services, and always have a backup plan because they will get shut down when you least expect it.

It's also a way of sending a market signal. If enough people start hesitating with adoption and promotion of Google services, they might finally eventually notice something is wrong and change their ways.