That can happen. text() is written into 3D space in a fixed location in data coordinates, and when you rotate, it is possible for the location to become hidden behind the object. That is expected to some degree: if you were to label cities on a globe then as you rotated the globe you would not typically want the cities "on the other side of the world" to have visible labels.
Reducing the alpha of the graphics object can reduce the problem, as then the graphics object does not hide the text as easily.
Sometimes, though, what you need is two or more axes, possibly linkaxes()'d, one containing the graphics and the one in front containing the text, since the one in front will overlay the one behind even through they are in the same data plane.
Or sometimes you should just use data tips.
