Repeated modification does not modernize a weak submarine design

What stands out about the modern North Korean Navy?

The fleet needs major improvement, especially after repeated efforts to rework the same conventional submarine design without curing its basic shortcomings.

North Korean naval development is difficult to interpret because much of the surrounding policy appears opaque or illogical from outside. The concrete criticism here is the submarine programme. The navy repeatedly returns to the same SSK design and adds equipment without producing a genuinely better boat. Successive modifications do not equal modernization when the underlying design remains weak.