WWE careers involve traveling around the world to perform, dealing with potential injuries in the ring, and developing storylines and rivalries with other wrestlers. Rey Mysterio's career is used as an example, as he developed a distinctive mask persona that boosted his popularity, had to undergo knee surgery after being injured by another wrestler, and went on to win championships while also feuding with rivals like Jack Swagger over title opportunities. WWE handles payment and expenses for wrestlers so they do not have to worry about finances while focusing on their in-ring performances and story arcs.