The world can be divided into serious and recreational readers - serious readers are re-readers: they read mostly in order to find those books that they can re-read. The rest are the recreational readers.
It is interesting to speculate on what it is that can make re-reading - especially the second time around - even more enjoyable and satisfying than the first reading.
The first time I read a book there is a part of me holding-back, waiting to see if the author can be trusted. Because if I open my heart to a book, and then it betrays me... well, that can be a wounding experience.
(Like confessing your innermost thoughts - then having them used to mock you.)
There are, after all, many books that at first seem to be one thing, and yet are another - books that start off apparently going one place, but end up somewhere much worse; books that fill you with hope until they turn, strike and eviscerate you with disgust or despair...
Most commonly there are books which build towards something, but in the end cannot deliver whatever it was, and fizzle out into... well, nothing much at all.
Therefore, during the first run-through I tend to hold-back, and wait to see whether this is a book that will deliver on its promises; whether this is a book which is of good motivation and honesty.
After I have read a book - I know the answer; and if it is a good book, then I always want to re-read it - this time giving myself fully to the experience, opening my heart to the book.
It is rather like meeting someone for the first time compared with subsequent meetings, On the first meeting both sides hold back something; and it is only as trust builds that we open ourselves to each other. Friendship with a real friend therefore gets better - whereas for the mass of others, an impressive or entertaining first impression inevitably yields to cumulative disillusion, boredom, irritation, repulsion...
Most of modern life is all about making striking 'first impressions' - including a serious concern with even the assumed-impressions we make on strangers who glimpse us in the crowd. Much modern literature: the same - engineered instantly to impress.
And as with encountering people, we ought sometimes to read for long-term growing friendship; and not always consume interactions with books in pursuit of instantaneous distraction - not always reading for one-off entertainment, thrills or consolation - or else we will never know any books, and find ourselves without friends among the library.