Hi Melotte, welcome to the forum.
The VRDB will generate a new version every 21 days, by default. During the time it is generating, the icon (animated with moving arrows) will show when the computer is idle. (Or only when the screensaver is running, if that option is selected.)
It can take an hour or more for generation to be completed. After that, you shouldn't see the icon again for another 21 days, unless you manually activate generation.
Does that fit with what you are seeing?