Explanation: Cause they only output sound, and are devices, further more they are not used to output images, like how could speakers output images using sound? They can't.
There has been a need to explore the different regions across the globe in the early ages, as there were ships to travel but there was no one before who knew about the different routes and maps of the region, so, it was sort of blind folded traveling when some one wanted to go far distances yet some of them knew about other regions on the far sides of many seas having a unique culture, different languages, along with having diversity among the flora and fauna inside the region.
So, like many other curious people across the globe there was a need for the people to explore all the regions. As, it was a need for the travelers and all the rest of free fork to know about this world. Now, every wanted to know more about the different lands but there were few who even performed the great feat, as they had fear for their lives.While, Christopher Columbus was more into sacrificing his own life in order to explore the lands at the far lands across the Pacific ocean. As, he arranged his mind and covered all the required arrangements for the journey.
As, was at first wanted to explore the lands of far east and thus wanted to more about the Subcontinent India, but in turn he reached the lands of the American continent in far west.While, upon arriving the American region we say many people with different skin tone, culture and language which was very different then he heard about the people of India.There was more different world then he could ever think of as he had a lot to tell about these lands upon the way back to Europe or his home land.
