Luger Magazine numbering

[Puretexan]

I can't see why they would have numbered magazines. If any of them fit any pistol, why would they have wasted resources, to make the magazine number match the pistol.
I can see a German soldier running around his barracks asking who has 2917 magazine, because at the range somebody swapped it for this 3418? Surely in the building process nobody though eventually a person would want the magazine that was originally assigned to this pistol.