The treaty category created the Hipper requirement

Why did Germany build the Admiral Hipper class when its purpose was less clear than that of the Deutschlands or Bismarcks?

The Anglo-German Naval Agreement encouraged Germany to fill the same eight-inch heavy-cruiser category used by other navies.

The class was a treaty-induced procurement choice. Once Germany accepted a tonnage share by category, naval planners had an incentive to use the available heavy-cruiser allowance. That produced ships comparable in armament to foreign treaty cruisers even though Germany's strategy demanded long-range raiders and mutually supporting task groups. Hitler later discarded the agreement when its limits no longer served his purposes, but the Hipper program had already absorbed resources. Arms-control categories can shape fleets even when the resulting ship type is a poor match for national doctrine.