Best practices for structuring Trigger handlers vs. putting logic directly in Apex Triggers?

 Hi Trailblazers! I'm currently diving deeper into Apex development and building out modular code patterns on Trailhead. For those working with enterprise codebases in production, what is your preferred design pattern for organizing trigger logic (e.g., the Trigger Handler pattern, helper classes, or specialized frameworks)?  

I'd love to hear what has worked best for maintainability and test coverage!