Nine Steps of Learning by Refactoring

I was asked on Twitter recently how is it possible to refactor if one doesn't understand how the code works. I replied that it is "learning by refactoring." Then I tried to Google it and found nothing. I was surprised. To me refactoring seems to be the most effective and obvious way to study the source code. Here is how I usually do it, in nine object-oriented steps.

[image error]Dom Hemingway (2013) by Richard Shepard

According to Wikipedia, code refactoring is "the process of restruc...