I'm manaheim here. If you were going for a poorly composed, photo with a blurry object smack dab in the middle of the frame, then this was 100% successful. Motion blur can be a fun thing, and this is a good experiment more than anything else. I imagine you were on a tripod (I could be wrong, of course). Compose your shot first, next time. Taking care to take everything in consideration. The composition is distracting with the stairway basically splitting the frame in half. Keep the rule of thirds in mind. If this blurry person was there as a model, and not just a random person walking (dancing?) by, try a lot of different things. Have them move in different ways. See if they can make some interesting shapes with their body and the motion blur. Experiment with different shutter speeds. See what effects you can make. But first and foremost, ensure you have a good composition.