What matters is not how much you write, but how much you rewrite

I first read Ventakesh Rao’s tips for advanced writers almost two years ago, and I still think about his advice to this day.

One of my main takeaways is that the difference between an amateur writer and a serious writer is the amount of time spent rewriting. Rewriting is where serious writing happens.

His entire answer is worth reading in full on Quora.