When addressing this question to someone who is engaged in writing, the first thing that comes to mind is that he will say "I like reading because I like writing!
But, indeed, the reader who reads for the purpose of writing is merely "transporter of messages", or "circumstantial writer" and not an original writer. If such circumstantial writer was not preceded by other writers, he has never been a writer at all, and if no one had said something before him, then he will has nothing to say to readers.
I love reading because I have one life in this world; and one life is not enough and do not move everything in my conscience of the motives of movement. Reading alone is the thing that gives me more than one life in the lifetime of one human being, because it increases this life in terms of depth, however it cannot prolong life in terms of calculation.
I do not like books because I lead an ascetic life, but I like books because one life is not enough for me. Whatever man eats, he will not eat by more than one stomach. Whatever he wears, he will not cover but one body, and wherever he moves in the countries, he cannot be in two places. But by thought, feeling and imagination, man can bring lives together in one age. He can also redouble his thought, feeling and imagination as the feeling of mutual love multiplies and the image doubles between two mirrors.
On the other hand, books are thought food, and there are various foods for every thought, as there are various foods for every structure. The advantages of a strong structure are that they extract lunch for itself from every food, thus, strong cognition can find food in every topic. In my opinion, the selection process of books is like selection process of food, both are only for a child or patient in this section. So read what you want, you therefore will gain benefits if you have a strong intellect or mental stomach that can digest the topics it receives, otherwise make your desire the factor of selection because body is often fed according to appetite.
Books do not replace the experiences of life because we need a share of experience to acquire the true understanding. Moreover, the experiences of life do not replace the books, because books are the experiences of thousands of years in different nations and ages, and the experience of one person cannot extend but some dozens of years.
I do not think that there are duplicate books because I think that if one idea has been dealt with by thousand writers, then such idea will become thousand ideas, and will be no longer one idea. So I deliberately read the words of many writers in respect of one topic and I feel that this is more enjoyable and useful comparing to reading various topics. For example, I read the works of more than 30 writers in Napoleon's life, and I am sure that each writer described the life of Napoleon is different from the description in the other books.