You cannot predict any unfortunate event hence it is advised to ship owners to have CO2 & marine CO2 systems present on their ships at all times. Even the smallest fire that breaks out can turn to a huge ball of fire which would risk the safety of the passengers and the ship itself. A short circuit can happen even in the middle of the night when the passengers are asleep or if the ship is docked and there’s no one on board it. When there aren’t people alert to handle the flames on their own, how do you expect the fire to be controlled if it happens?