Writing isn't a natural form of expression for most people. Even though many try, there's a difference between a someone who writes and someone who expresses themselves through the written word. It's not in the vocabulary or grammar, but the emotion put behind each word. Real writers "write drunk and edit sober" as Hemingway once said. They expose their heart and soul on the page, pens dripping with the visual emotions of the prose.
They might write with an agenda. They might write because they want to. It might be short or it might be long. It might look like scribbles or be neatly typed and bound.
One thing is certain however... Writing for these people is not optional... for it is through this expression that their true self journey is experienced.
I know because I write.