Be WET between modules, DRY within modules

DRY (Don't Repeat Yourself) WET (Write Everything Twice)

DRY has been an admirable rule, but the most significant application of it had meaning 2-3 decades ago when everybody had to care about the result size of the source code.

But still, it is a good practice in SOME PLACES. Like, you have a class and an implementation that repeats a few times in this class. This is a sign that you should apply the DRY.

Check out my simple diagram what is the goal and importance od the WET.