When handle objects are released created inside static methods

I have played with the example code showed in https://se.mathworks.com/help/matlab/matlab_oop/example-using-events-to-update-graphs.html

In the static function createViews of class fcnview, 7 fcnview objects are created and 4 of them are saved in the array fcnviewobj. I have some questions:

1. Why the 3 objects in the array fcnviewobj which are replaced in the last 3 loops are not released/destroyed since no one will use them. (These 3 objects are released after the figure is closed.)
2. Those 4 objects in the array fcnviewobj are not released after the figure is closed, why? (They are not released even I call fcnview.createViews again.)
3. How Matlab manages these kind of variables?

Thanks a lot!