What made an early torpedo difficult to build

The early Whitehead torpedo, developed with the Austro-Hungarian Navy and later adopted by the Royal Navy, combined a warhead, propulsion fuel, an engine, and straight-running controls. By about 1904-1905, the example under discussion could travel roughly 1,100 yards at 35 knots, a useful benchmark for the tactical limits explored later. A torpedo had to remain balanced as it consumed fuel, so changes in weight, buoyancy, pressure, and by-products could send it off course. One claimed compressed-air balance effect remains scientifically uncertain. The engineering was demanding. The claim that a torpedo was inherently more complicated than an entire battleship belongs in a film, not in a technical comparison.