She hated when she came to the realization after the fact that Alecto had been at least partially correct. Sometimes she did just assume that her way was best and would hear no argument claiming otherwise. Her ill-fated crusade to free the house-elves came to mind. Because she believed they were all miserable and mistreated, she had to save them from their existence. No matter how many times she heard from others, including the actual house-elves themselves, that they were content and even happy, because they disagreed with her, she believed they were wrong. Opening up her closed mind to different possibilities was difficult.