Why refactor? Because it's the mark of a pro. If you need more reasons, try these:
Because we know what it is like to read and debug a 500 lines method. And we don’t want to go through it again.
Because we’re sure the other guy's code can use improvement. Even if they thought otherwise.
Because we can’t think at the same time about both the solution and its readability. Even if we think we can.
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