Because to confide a part of your soul to something that can think and move for itself is obviously a very risky business.
J. K. RowlingThe presence of hundreds of books had finally convinced Hermione that what they were doing was right.
J. K. RowlingMinistry of Magic (M.O.M) Classification. xxxxx Known wizard killer / impossible to train or domesticate / or anything Hagrid likes
J. K. RowlingSo,โ sneered Fudge, recovering himself, โyou intend to take on Dawlish, Shacklebolt, Dolores, and myself single-handed, do you, Dumbledore?โ โMerlinโs beard, no,โ said Dumbledore, smiling. โNot unless you are foolish enough to force me to.โ โHe will not be single-handed!โ said Professor McGonagall loudly, plunging her hand inside her robes. โOh yes he will, Minerva!โ said Dumbledore sharply. โHogwarts needs you!
J. K. Rowling