#3 Gail Kim
Gail Kim may go down in WWE history as one of the company's biggest blunders.
Joining in 2003, Kim won the Women's Championship on her first night, though quickly became an afterthought, leaving years later due to feeling under-utilized.
Things didn't go much better for Kim when she returned in 2008, with the TNA Hall of Famer admitting that this return was mainly for financial stability.
In TNA though, Kim became one of the biggest stars ever, becoming the company's first Knockouts Champion before retiring a few years ago, as one of the most decorated stars in the promotion's history.
Nowadays, Kim continues to work for Impact, though in a backstage production, where she has been cited as one of the main factors behind the company's recent success after years of uncertainty.