Lost the sense of direction
Frank Pearce, one of the founders of the company, the vice chief inspector of game development once said at the beginning nobody would like to spend a penny on it and it would just turn to be trash. But later Star Wars Galaxies credits were he who was deeply absorbed in playing the game after work even on weekends. That means you already partly succeeded. Every now and then a question would pop up in your mind: can we make it bigger? Or it will be just an idea go bad? During the process of development some frustrating thoughts would haunt you like what if the game would fail or it was not interesting at all, especially after you lost the sense of direction of a long cycle of development.