Imagine a worst case scenario... Shenmue III is not succesful and doesn't get too many sales. Thus, SIV is not feasible, but Yu Suzuki and the fans, want the final chapter of the saga made. Would we be able to gather enough money to create a game that would probably be bigger in scope than 3? Outside financial backing would be even more difficult to get then.
I shudder just to think of it, so I'm going to start saving money just in case.