The big problem we face is apathy among voters. But bigger than that is the fact that when we find a really good and solid conservative that the machine in DC can't pull away from conservatism, we want to keep them in office as long as they will serve.
In addition to that - a newly elected rep does NOT learn the ropes for almost two years. Some coming from state legislative experience 'get it' in far less time. Others are green as a gourd for up to two years, and have to be led around by their staff - often voting non-conservatively at the advice of others - not even knowing that they are voting on the wrong side of many issues.