How clean should new code be? [duplicate]

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• How would you know if you've written readable and easily maintainable code? 19 answers

I'm the lead designer in our team, which means I'm responsible for the quality of the code; functionality, maintainability and readability.

How clean should I require my team members' code to be if we are not short on time?

In my view, we should clean up old code we modify; adding a line to a method means you clean up that method.

But what about new code?

We could make it sparkling clean, so that if another coder comes along tomorrow and makes a small modification, she doesn't have to clean it up at all. But that means if no-one ever reads that piece of code again, we've wasted time making it sparkling clean.

Should we aim for "almost clean" and then clean it up further on future visits? But that would mean not getting the full value for the understanding we had when we wrote it in the first place.

Right now, I'm going for "sparkling clean"; partly as a tutorial for my colleagues who are not as picky as I.