"For books, timing is everything. The moment you first encounter a particular book is the right time to read it. To avoid missing that moment, I recommend that you keep your collection small."
Marie Kondo, The Life-Changing Magic of Tidying.
The chapter on the place books have in our homes and in our lives provides advice and food for thought: for example, regarding unread books, " 'sometime' means never", Marie Kondo says; sorting your books with a view to disposing of some requires you to move all of them from shelves to floor and then pick up each in turn and gauge your reaction to it as you handle it (she explains why this method works); she suggests keeping a small collection which she calls 'the personal Book Hall of Fame', and any book which gives only "moderate pleasure" should forfeit its place on the shelf; and she reports from personal experience that having fewer books "increases the impact" of what one reads.