Self-knowledge is key for a writer. One reason (of many reasons) it's so important is that knowing your weaknesses is a necessary first step towards overcoming them. One of my own weaknesses (or, optimistically, "features") as a writer is something I am coming to think of as a second chapter Novelist's Gearshift.
In songwriting, a truck driver's gear shift is when the songwriter (producer, etc.) shifts the key up to keep the listener's interest. See here. This is done on purpose.
My Novelist's Gearshift, by contrast, is something I do on accident. I find that it usually takes me until the second chapter to find the right gear for a story (my wife will tell you that I drive the same way). Specifically, I tend to overwrite the first chapter (sentences too long, writing too flowery or intense). Knowing this about myself, I take extra care in reviewing and revising my first chapters to compensate.