Why the Deutschland class could burden its own navy

Why describe the Deutschland class as a particularly troublesome German warship design?

Because it was capable enough to require real employment but worked in ways that complicated both German planning and its opponents' responses.

The Deutschland class is more troublesome than a merely useless design. It worked well enough to become part of naval plans, while its unusual capabilities and limitations made those plans harder to execute. That combination could burden the navy operating it as well as the enemy reacting to it. Institutional and operational fit can matter as much as whether a warship's machinery functions.