Some of it has to do with your location. In the larger metro areas where there is more work available, you would have better success finding work as an assistant. Take New York for instance, it is a breeding ground for new talent but very hard to become established in the trade. Those that are established are not afraid of new talent, because they know you will have to work your butt off once you strike out on your own, and the clients are fairly loyal once they find a photographer they enjoy working with.