Why copied warships still differed from their models

A navy can copy a captured ship while changing the design to meet its own needs. The comparison with the Napoleonic wars contrasts French ships built for speed with British requirements for sturdy hulls and prolonged service in difficult seas. British adaptations needed more room for food and supplies, which favoured a fuller hull. Roman quinqueremes likewise remained heavier than their lighter Carthaginian counterparts. They were slower and less manoeuvrable, but their stronger hulls tended to withstand ramming better. Adapting a design could therefore preserve a navy's priorities while incorporating lessons from an opponent.