Some players just aren't worth it. Managers can spend weeks, months and even years trying to extract that finest nuance of talent from their being, but if the application or work-rate isn't there, they won't survive in the rigours of top-flight football. As the wise Joey Barton once said, 'in the top level of world football, if you're not prepared to work hard, you will come up massively short'. Known for his pearls of wisdom on social networking sites when keeping himself out of trouble, the player in question whom he was referring to indeed features on this list. Of course, there are other reasons why certain players who signed on the dotted line at White Hart Lane weren't worth the trouble. Aside from unprofessionalism and lazy work ethic, some footballers simply didn't settle in North for a myriad of external reasons. However, in each case documented here, there was certainly a degree of unprofessional behaviour which kept these players from realising their full potential, and instead caused the Spurs board and management more headaches and trauma than they would have wished. Take a look at the ten players listed, who for all their undoubted talents and abilities, gave their managers, chairmen and PR team a number of sleepless nights.