Almost no one believes they deserve criticism. Al Capone thought he was a public benefactor. "Two Gun" Crowley wrote, while bleeding from police bullets, that he had "a weary heart, but a kind one." Every criminal at Sing Sing prison had a story that justified what they'd done. This is not a quirk of criminal psychology — it is universal human nature. Ninety-nine times out of a hundred, people don't criticize themselves for anything, no matter how wrong it may be.
This is why criticism fails. It doesn't reach a rational mind weighing evidence; it hits a person who is busy protecting their sense of being good and right. The result is almost always the same: defensiveness, justification, resentment toward the critic, and no change. Theodore Roosevelt's public attacks on William Howard Taft didn't change Taft's mind — Taft wept and said "I don't see how I could have done any differently from what I have." The Teapot Dome scandal, public humiliation, prison — Albert Fall's wife still insisted her husband had been "betrayed and led to the slaughter."
B. F. Skinner showed in controlled experiments that animals rewarded for good behavior learn faster and retain more than animals punished for bad behavior. Later research confirmed the same holds for humans. Criticism doesn't produce lasting change; it produces resentment. As the psychologist Hans Selye put it: "As much as we thirst for approval, we dread condemnation."
The mechanism
Criticism wounds pride. Pride is not a minor thing — it is close to the center of how people experience themselves. Once you wound it, the wounded person's entire energy goes into self-defense: marshaling arguments, finding fault with the critic, retreating further into their original position. John Wanamaker, who founded the department store chain, said he learned early that "it is foolish to scold." The criticism might be factually correct and still accomplish nothing except damage the relationship.
Lincoln understood this. As a young man he wrote mocking letters and dropped them on country roads to be found. One letter too many led a man named James Shields to challenge him to a duel. Lincoln came close to dying over it. After that, he almost never criticized anyone publicly again. When General Meade disobeyed his direct order at Gettysburg and let Lee's army escape — potentially prolonging the Civil War — Lincoln wrote a scathing letter and then never sent it. His reasoning, Carnegie guesses, was that sending it would relieve his feelings but make Meade justify himself, condemn Lincoln in return, and perhaps force his resignation. The letter was found in Lincoln's papers after his death.
What works instead
Compassion and understanding can accomplish what criticism cannot. Evangeline Booth arrived in Skagway, Alaska — a lawless gold rush town — and met Soapy Smith, the "Killer of the Klondike." She didn't condemn him. She listened to him talk about his childhood and his grandmother and his regrets until dawn. He wept and promised to change. She reached a hardened murderer by doing the opposite of criticizing him.
Bob Hoover, a famous test pilot, once had his plane fueled with jet fuel instead of gasoline by a mechanic. Both engines failed at 300 feet. Hoover landed the damaged plane without killing anyone — then walked up to the trembling mechanic, put his arm around him, and said: "To show you I'm sure that you'll never do this again, I want you to service my F51 tomorrow."
The safety coordinator who asked workers why their hard hats were uncomfortable got compliance; the one who told them they must comply got sullen acceptance and hats removed when he left.
The alternative to criticism is understanding: try to figure out why they do what they do. That breeds sympathy, tolerance, and the conditions where change can actually happen. Carnegie's formulation: "Instead of condemning people, let's try to understand them."
Limits
This principle does not mean pretending everything is fine or never addressing problems. It means approaching the problem from the other person's point of view — letting them save face, giving them a reason to want to change — rather than attacking their behavior directly. The goal is the outcome, not the relief of expressing frustration.
There's also a narrow category — direct feedback someone has requested, or safety-critical corrections — where the principle bends. But even then, how the feedback lands depends entirely on whether the person feels respected or diminished.