Sorry I don't understand French, but I think I get the gist.
Personally, I don't like locked up nonconforming material areas. If I lock them, how can the nonconforming material freely move INTO the area? I've fought this with many customers, and I generally win.
NCM areas are defined. ANYONE can put material INTO the area. Only certain people can move material OUT. Once this is defined procedurally, it becomes a training issue.