Many readers maintain a constant surplus of books from which they may choose what to read next. The idea of a to-read-pile for some is literal; for others it is figurative. Different people have different approaches to their to-read-pile. My pile is figurative. I know that I have a home full of books, some I have read, many I have not. Of those I have not read, I do not even plan currently to read each and every one. I do not plan too far in advance, the order in which I will read my books. When I am nearly finished with the book I am reading I will pick what will be next. And for people who finish a book with no plans to even go to their local library to choose the next one, I do not know how you do it. You are stronger than I. I will actually not finish a book until I have picked what is next so at the moment I am ready I may pick up the next and get started. Finish one book, reflect, start the next.
Using a literal to-read-pile where you have an actual order for the books you will read subsequently is not for me. A lot of which book I choose depends on my current mood and how busy I will be for the upcoming week or two. If I know I will be swamped I will try to choose something that is lighter; an easier read. If I know I do not have many things scheduled I might try to tackle a book that requires a little more time and attention. It is very difficult to plan that more than a book or two in advance.
I have a difficult enough time when I travel. If I am going away for an extended period of time (3+ days) I try to pack in a "just in case" manner. It is funny when I am able to discuss this approach with other reader travellers. I take the book I am reading and one, two, maybe even three more books. The number of books then will depend upon number of pages, writing style, content and of course how much time I will have to devote to reading on my trip. The time I have available to read starts with a wait in the airport before each leg of my trip and then each leg of my round-trip flight. It is hard enough choosing a small handful of books to bring along when I fly, let alone planning say months in advance. Have I ever finished that many books on a trip? No. Why take so many? Because I can never not be reading a book, even though I am not always actually in the act of reading it. I guess it is a character flaw.
I am not sure I could ever, and I know I would never, try to place a stay on my book buying. Sure I have a lot of good books at home that I have not yet read, but there is so much excitement in buying new books. The idea of "I will not buy another book until I have read every book that I currently own" does not appeal to me. I have a company in New York that sends me books monthly and I generally treat myself to an order from Amazon.com every month or two.
When those packages arrive I am like a kid on Christmas. Even though from Amazon I know what is in the box, I cannot wait to get it open. Why place a hold on that feeling? I cannot find a reason to do so.