He doesn’t have to. He’s decided to because he’s motivated to play and prove himself for a prestigious club. He was a disgrace at Woolwich.
Indeed. He had issues with mentality/ego at Dortmund too. Clearly at some point at Woolwich he decided he wasn't particularly interested, and once that happens the manager has little to no choice. Just because he's doing well at Barca doesn't mean Woolwich were wrong to let him go.