Dependency injection was a fad. Pretty much every framework under the sun started using it and exposing it in the API and now it has more or less fallen out of favor, giving way to other fads such as framework metaprogramming. Following fads has little to do with writing good code the first time around. Good code is code that gets the job done, has some modicum of maintainability, and didn't take you 10 years to write perfectly the first time.