Think twice before make big refactoring to code is new to you

"...[existing code] rewrites should be avoided because the programmers will not have been able to understand from the code why the software does what it does and, when rewriting, will revisit all the same mistakes the original programmers made. The same can be said [...] about making big refactorings to code that is new to you when you are not adding any new functionality to the system. It's only by adding a new feature that you can get a feel for the structure that the code needs to have. Otherwise you're just noodling about aimlessly and your refactoring will very probably make itharderto add new features in the future." Nat Pryce

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