On her site, casfic raised an interesting point about the difference between what you write and what you read. I encountered exactly this when I started this motives-and-writers research.
There's a bit of research on what people with a given motive pattern like to read for pleasure. Since motives are about what you enjoy, logically you will read things for enjoyment that align with your motives. This led me to believe that writers of a given genre would have the motives of a reader of that genre.
I was wrong.
In brief, here is what the typical reading profile is of someone high in a given motive:
Achievement motive: nonfiction, how-to, (things you can learn and improve from reading), "puzzle" mysteries like Agatha Christie or Ellery Queen that may be stronger on plot than character.
Affiliation motive: stories about characters and relationships, romances.
Influence motive: nonfiction about influential people (biographies of leaders, history), psychology, theology (the ultimate power relationship!), political thrillers, "hard-boiled" (private eye) mysteries, stories with more sexual and violent content.
Science fiction could be in Achievement or Influence, depending. I think most fantasy is in Influence, with a touch of Affiliation.
So naturally I thought this would align for writers as well--you write what you read, right?
Wrongo! Virtually all the published writers I have studied have the same motive highest: Influence. These people write in order to be read, which is a form of influencing others. So perhaps the Regency Romance writer (for example) is getting influence satisfaction about inserting into that world or doing the historical research or knowing s/he will impress people with a new niche instead of just enjoying the romantic relationships themselves.
This disconnect is a bit mysterious to me at the moment, but I feel sure it can be noodled out.