Sometime one must coax what out.
Each day is really a battle to sit prior to the computer and produce--produce words which are appropriate, produce sentences which are logical, produce paragraphs which are focused, and create a page that's highly relevant to the project--whether this is a poem, a brief story, articles, an essay, or section of a novel.
Once the determination was created to sit and produce, then your output seems easier even though you have to wrest what from the blank mind. Once started, the flow becomes inevitable, even though ideas might not be that which was intended or planned. Sometimes, it means that one isn't in command, and at other times one isn't.
Sometime one must dredge what from the soul to create something, anything, but one must make an effort to maintain control and centered on the piece that certain has in mind even if it really is only an entry in a journal, a diary, or perhaps a forum of any sort.
If the writer specializes in communicating with the intended reader, the ideas should come, and when the ideas come, what expressing them may also come. This is the nature of writing--to share ideas with others.
So whether you need to coax, prod, or drag what, the sentences, the paragraphs out, the important objective would be to develop a composition which will be a satisfactory expression of the writer's thoughts.