People go quite still when I say their name across the room. It reads as correction, and it activates something old and school-shaped in most of us.
What it usually means
That you are doing something worth adjusting, which requires that you are close enough for the adjustment to land.
I do not spend refinements on people who are a long way off. If you are well outside a position, the useful thing is a different position, not a refinement. You get the refinement when the shape is basically there.
Being corrected repeatedly is a signal about proximity, not deficiency.
The other reason
Safety, and that one is not subtle. If a teacher moves quickly, uses a different tone, or gets you out of something, that is not the same event and you will be able to tell.
Why not just come over quietly
In a full room they cannot get to everyone, and a spoken cue reaches four people who needed it and only names one. It is efficient rather than personal.
There is also the fact that many corrections are easier to make than to receive physically, and saying it lets you find it yourself, which sticks better than being placed.
When nobody says anything to you at all
This is the one people should worry about slightly more and never do. In a large class it usually means the room is busy. In a small one, over several weeks, it is worth asking directly.
Ask me whether there is something you should be working on. Almost nobody ever does, and it is the best question anybody asks me all week.
The reframe
If your name comes up, you are being taught. That is what you paid for.
The class where nobody notices you is the comfortable one, and comfortable is rarely where anything changed.