I cared about you too much,” said Dumbledore simply. “I cared more for your happiness than your knowing the truth, more for your peace of mind than my plan, more for your life than the lives that might be lost if the plan failed. In other words, I acted exactly as Voldemort expects we fools who love to act. Is there a defense? I defy anyone who has watched you as I have — and I have watched you more closely than you can have imagined — not to want to save you more pain than you had already suffered. What did I care if numbers of nameless and faceless people and creatures were slaughtered in the vague future, if in the here and now you were alive, and well, and happy? I never dreamed that I would have such a person on my hands.
J. K. Rowling, Harry Potter and the Order of the Phoenix