Product Judgment is a learned skill that exists to help individuals accurately predict what customers need, want, and value. It's not innate and takes years to build, ranging from weak to strong. Great Product Managers and Designers have strong Product Judgment due to their understanding of how to get it through deliberate work and dedication. This judgment can be applied in various areas such as roadmapping, scoping, designing, and making roadmap decisions. To obtain Product Judgment, one must have direct experiences with customers, observing and talking to them widely to cover different domains. It's a never-ending journey, and building strong Product Judgment requires continually checking and refining it. With experience, one can build strong judgment in specific domains, such as industry or product areas, but it's not transferable across different domains. The process of building strong Product Judgment involves falling in love with talking to customers, overcoming inhibitions, and pattern matching to accurately predict customer behavior.