There are many reasons to build/create better aircraft designs, including but not limited to, Fuel economics(to save fuel), weaponary improvments, and distance travel. There is no perfect airplane, and we will never find one. The reason why we make better aircraft, is to improve on our designs, and because we constantaly can find better ways to improve things like, fuel economics, and space/storage.
<em>The British and their colonies were able to trade without exchanging gold or silver, and the ships' owners (who were British) were able to make a profit at every leg of the journey. </em>
