Why do writers write? John Updike said that writing was his, “sole remaining vice. It is an addiction, an illusory release, a presumptuous taming of reality.” It could be that they have something really important to say. Or, it may be that they’ve spent one year researching a particular subject, and they build a historical or factual novel around imaginary characters.
The preceding are practical reasons; but there may be those that write out of need because, to not write, is too psychologically devastating; the pressure of whatever it is they have to say becomes to great and it causes great mental perturbations that can only be relieved by sitting alone and writing what he/she dare not say in public. Or, maybe a writer puts his or herself into a variety of situations through travel, or living out of the shadow of the norm, and they must tell of it. It could be that the need to write is a manifestation of a love affair with solitude. Perhaps one can only write out of conflict.
I feel much like Mr. Updike in that I feel I can say anything I want in a room with a view of the sea. The ocean and wind and clouds all going about their business as I deposit, via ones and zeros, the extraneous inner personal casualties fallen in the line of duty while living in a hazardous society where saying exactly how you feel is frowned upon.