We obsess about writing skills as a culture, and yet, almost never talk about reading skills. If people suck at reading they will suck worse at writing. And the internet has destroyed most peoples reading comprehension and attention.

Or put positively, if you want to improve your writing, read, a lot. Learn how to read analytical, for pleasure. Read stuff you dislike, disagree with. Understand why. Without a well developed sense of taste and comprehension, writing skills will never improve.