The document discusses modernizing JavaScript development in Plone by making code more modular, tested, and maintainable. It promotes writing JavaScript using AMD or CommonJS module patterns and managing dependencies and updates with tools like RequireJS and Jam. The document also advocates for writing tests with frameworks like QUnit, Jasmine, Buster, and Mocha and using an assertion library like Chai or should.js. Testing, modularization, and dependency management are presented as ways to improve code quality, make debugging and updates easier, and allow add-ons to integrate more seamlessly.