Normal
They have a culture of everything being a beta and so they discard them at will. In addition, they offer the software for free they don‘t obligated to provide it when it’s no longer something of interest to them. I also wouldn‘t be surprised if a lot of these softwares are basically studies to see people’s behaviors. Google‘s value is in the profiles it builds on its users and they may need some particular data so they come up with an app, get the data they need, then shutter it. Like all the captchas we see where it asks you to click all the taxis, thats just us helping machines learn to recognize things in images.