It’s a bit of code that the smartthings app uses to control the way the device information is displayed in the app.
Whenever there’s an update to that code, you will get that message.
So you might not see the message for a particular device for a year or more, or you might see it a couple of times in a week if they are fixing bugs.
It’s not updating the device itself, just the displayed controls in the app.
We were just talking about this in the forum a couple of weeks ago.