I worked for another large defense contractor auditing government IT systems. To do this, you needed a clearance and auditing certification designed by the gov. Well, they would just go ahead and hire people WHILE the clearance process went through (which can take months) and only schedule certain technology certification classes every few months. There were people sitting at home for 4-6 months getting paid in full while they waited for either a class or their clearance to go through. I sadly already had a clearance and "only" had to wait a month for my class.