I think I was on the cusp of this realization for quite some time, and after reading the first five Harry Potter books back to back in such a short time (just two and a half weeks!), I had to make it official.
Of the first five books, Harry Potter and the Order of the Phoenix is my favorite.
Yes, even over Goblet of Fire.
I don't know if I can even give a good explanation as to why...maybe it's my fondness for the fact that Phoenix is the Empire Strikes Back of the Harry Potter series. It angers and depresses me from beginning to end. As evil as Voldemort is, as bad as Bellatrix Lestrange is, as frustrating as Snape is...Umbridge is, in my opinion, the worst Harry Potter villain. And as much as this should maybe make me hate this book, it appears to have the opposite effect.
Then there are the good parts, the really good parts--the formation of the D.A., Christmas in St. Mungo's, Fred and George's glorious exit from Hogwarts, and even the chapters when they are in the Department of Mysteries.
My point is...I can understand, what with the length and the depressing aspects and above all, Umbridge...why many people wouldn't or don't like this particular Harry Potter installment.
But me? I love it. I was still refraining from calling it my overall favorite HP book until I'd finished the final two installments--but I absolutely knew it was my favorite out of the first five.
"'Poisonous toadstools don't change their spots,' said Ron sagely."
'"Indifference and neglect often do much more damage than outright dislike...'"