It seemed to me that writers have an easier time of it finding commercial niches to work in --romance, true crime, history, mystery, DIY-- and that a good many large publishers have imprints that specialize in the various specialty markets; they (the publishers) are not limited to publishing only one writer , and the writer, though competitive, can also seek another publisher if circumstances warranted. The resources for writers are far less scarce than they are for architects: there are only so many clients with only so many projects and a finite amount of adequate funding.