“Don’t Repeat Yourself” is often taught and shared, but I find it to be not that useful and often wrong. The aphorisms about programming I find myself revisiting are:
First make it easy (warning: this could be hard), then make the easy change.
And
Make it run, make it right, make it fast.
What common advice do you find unhelpful? Which bits do you find yourself often citing and coming back to in your own work?