Dead End
The player has reached a Dead End when no actions whatsoever can carry the game forth, and the game progess is helplessly halted.
Dead-ends are generally impopular, since the game can be unnecessarily difficult to win, and any attempts to solve it will be a waste of time. Dead-ends occured primarilly in Sierra-games (several of the Police Quest games can go on long after a specific puzzle, but are yet impossible to beat if the puzzle in question is not solved properly), and are very rare in e.g. Lucas-art games, if they exist at all. See also Walking Dead