When all information is known, it should be clear what moves are available to each player. When there is some unknown information, it should be clear what moves are potentially available to each player.

In general, to avoid optimization problems, it is ideal to conceal some of a player’s information during a game. If some moves are secretly unavailable, a game is much more exciting.

What players must understand is what their opponents are capable of doing, as all tactics and interesting strategies rest upon the understanding and speculation of the motives and plans of other forces at the table.