One can never know what he or she is capable of until one explores outside of his or her comfort zone. This is especially true of writing. I never once thought of myself as a mystery writer, especially while I was publishing several books of poetry, and it wasn't until my wife pushed me to try it did I find that it was something at which I excelled. I never even liked that genre- sci-fi is what I mostly read.
I know of a man that never wrote fiction before he retired and when he turned seventy, he made a huge amount of money in erotica once he wrote his first book. Who knew?
I always tell novice writers to branch out in all directions before settling on a favorite genre. There is really no other way to judge all of one's talents.