While in theory true, in practice borders are not 100% effective. Locking the doors encourages people to climb through the windows, even islands can be entered

While in theory true, in practice borders are not 100% effective. Locking the doors encourages people to climb through the windows, even islands can be entered by boat. Opening the borders with a strict two week quarantine enforcement seems like the only sane way to proceed (as NZ has done)