Very simple: JS (module pattern, encapsulation) is verbose. CoffeeScript is more compact, allowing for more code on one page. I toy with going back to JS (I don

Very simple: JS (module pattern, encapsulation) is verbose. CoffeeScript is more compact, allowing for more code on one page. I toy with going back to JS (I don't like everything about CS, especially with debugging and test tools in node development) but CS optimizes for the good parts of JS and ignores the parts I don't want to use anyway.