I wanted to write spy fiction, create a character as loved as James Bond or Jack Ryan. I enjoy reading Reacher and Rain today, but the super-competent adventure character never seemed to ring true when I wrote it.
Crime fiction may come easier to me because everyone has at least thought about committing a crime, and the protagonists of crime novels don't have to be all that capable of committing the crime. I can also write dialogue-based stories as I'm very conscious of how people talk and the nonverbal stuff they reveal when they talk.
As a working poet, I find that many people who aren't into poetry have a specific idea what poetry is, usually associated with rhyme scheme or number of lines. And while poetry does require focus, it can be informal. Finding the truth behind a poem's subject and holding to that truth is the most important thing, just as in any type of critical or creative writing.