Doherty's Law states that a computer system is most effective when the user and the computer are both engaged in a collaborative effort. This principle emphasizes the importance of user involvement in the computing process, suggesting that systems perform better when users are actively participating rather than passively receiving information. The law highlights the balance between user input and system capabilities. When users are engaged, they can provide valuable feedback and insights, leading to improved performance and satisfaction. This concept is particularly relevant in fields like human-computer interaction and user experience design, where understanding user behavior is crucial for creating effective systems.