Ego is a huge human weakness. People struggle hard to admit they are wrong. This is especially true if they are committed to an idea that happens to be wrong. They would rather distort their own reality than admit they were wrong and try to grow from the experience. Once nice thing about being a scientist is we get lots of critical feedback from one another and we learn to admit when we are incorrect. However, even we are not immune. I know of one scientist who ruined their career committing to an idea that was wrong.