Paper was first created for the purpose of packaging and cleaning instead of writing, according to one of the senior engineers in China. (link in Chinese)
The first type of paper is hard to write, because it is made up of hemp. It is hard for the ancient people to write in ink. At that time, people found it is convenient to use the hemp paper to package stuffs. Also, they use the paper for the clearing after the human excreting.
The two function of the paper pushed the usage of the paper, and then people created the silk paper for writng, which is recorded in the history.