And the Trelawney award goes to.

[eggplant107]

No: HPFGUIDX 177127

My biggest failed prediction is that Harry didn't die. I do wonder if
JKR was ever tempted to write only 704 pages instead of 759; suppose
the last chapter was chapter 24 and the entire Potter story ended with
the words:

"He saw the mouth move and a flash of green light, and everything was
gone."

If she had done that there would have been riots in the streets, but
I'll bet JKR fantasized about doing exactly that.

My second biggest failed prediction is that Percy turned out to be yet
another (yawn) good Weasley. I still think JKR dropped the ball on
this sub thread. Suppose that instead of Harry stupidly verbalizing
the name "Voldemort" and getting everyone carted off to the Malfoy
Manner Percy had betrayed their location to He Who Must Not Be Named.
Fratricide is much more interesting than a slip of the tongue. As it
is I really don't understand why JKR invented Percy, maybe she got
cold feet and decided to play it conventionally.

 Eggplant