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That really depends on what you're working on and to what degree it's coupled to the system it's a part of. A form on a web application, or an API endpoint? Sure, rewriting it is probably trivial. A new process scheduler for Linux? The caching system in an HTTP server? Maybe writing the code will be easy (though probably not), but building any confidence that it doesn't break something that's unexpectedly load bearing will be anything but cheap. And if what you're rewriting that started out as "just code and see what happens" it's going to be more expensive still.

Which isn't to say that rewriting can't be cheap, but some intentional design (or at least diligent maintenance and refactoring) must have gone into the system to support that style of development. At which point you're back to targeting "quality," even if it's no longer a focus of on the smaller scale.