The H-1B program was established in the United States to attract foreign workers. To qualify for these visas, you must have specialized skills and have attended a foreign university. The H-1B visas are given out based upon a lottery system. Companies have found out that if they flood the application pool with thousands of visa applications for their potential employees, they have a much higher chance of being selected. This has negatively impacted small businesses who will only file one or two of these applications, which are rarely granted.
See "Large Companies Game H-1B Visa Program, Costing the U.S. Jobs", Julia Preston, November 11, 2015