I'm not much of a painter, but I sketch/color a good deal in both traditional and digital mediums, and I also write a lot. I find that both have their perks and drawbacks; it depends on how I'm feeling at the moment whether words or sketches will be able to convey the concept better.
However, I have a friend that I've talked to about it in length. He's an art student, and he said once, "There are a thousand words in a picture, and so that's where I choose to tell my stories." I just thought it was very clever, and it's stuck with me a while =)