7. Ryback - 12 Years
How can Ryback have been twelve years under WWE contract, and yet still be so unrefined in the ring? You wouldn't think Ryback was one of the longest tenured WWE veterans when you watch him, but he actually debuted all the way back in 2004 on the Smackdown Tough Enough. Although not victorious on the show, he was signed to a deal and went on to years of developmental hell. He finally came back to the main roster as part of the 2010 NXT show, going on to a run with The Nexus. In 2012, he returned from injury as Ryback, which actually elevated him to tremendous success. He was massively over at one point, only to tumble back down the pecking order in 2013 after losing his high profile feud with CM Punk. Despite being a company veteran, he's never really mastered his craft.