Why German destroyer problems were not just a stern-design issue

Did German destroyers leak because of their distinctive stern design?

Design mattered, but the broader explanation is uneven construction quality, rushed rebuilding of industrial capacity, and insufficient skilled labour.

The answer first distinguishes post-war German-operated Fletcher destroyers from the wartime German Z-designs named in the clarified question. Post-war yards had to relearn lost skills while adapting American construction and maintenance methods, whereas prewar rearmament rushed new German designs through an industrial base still rebuilding. Political will and money could not instantly create experienced welders, designers, supervisors, and reliable quality control. The resulting leakage and inefficient internal layouts show why impressive paper specifications are not the same as a shipbuilding system able to deliver them.