I have huge numbers of books in the house, and I have probably read about 75% of of the ones that are meant for reading rather than reference.
I do keep buying too many new books but I do also eventually get round to reading books that I bought years ago, so for example I am currently reading Infinite Jest, which has been sitting on my shelves since 1997.
Stockpiling books means there is always a book in the house to suit your mood at any given time 
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