In this job market, you might expect that hiring new employees would be easy. But many entrepreneurs still struggle to find good people. To be sure, not every candidate is a rock star. But if you keep turning up dud after dud, the problem may not be the applicant pool. In a quest to find the best workers, entrepreneurs sometimes wind up adopting hiring practices that are actually detrimental to their companies. Here are the four most common problems that afflict interviewers.