Human behavior often defies logic and expectations, making it unpredictable and sometimes unsatisfactory. People are driven by complex emotions and impulses that don't always align with rational thinking, leading to unpredictable actions and outcomes.
As Stephanie Perkins notes in her book, Isla and the Happily Ever After, human nature is inherently unreasonable. This unpredictability is a part of what makes people complex and, at times, difficult to understand or predict.