That is the essence of game design.  Games are about decision-making.  Historical games, for example,  need to put you in the shoes of an historical figure and present you with their choices.  The game then presents outcomes based on those choices until you reach the next decision point and on and on.

Too often, game designers get caught up in the mechanics of details instead of the mechanics of decision making.  If you've got good mechanics to handle the decision making, the details all but take care of themselves.

An example?  Columbia Games East Front 2.  I got an opportunity to play this a couple of weeks ago.  While a player has many decisions to make - including the usual in a wargame (where do I attack and with what), the core of the game is managing your HQs effectively.  The player who does the most with the least effort by his HQs will almost certainly win.  And the most efficient way to use HQs is not always readily apparent.  I was halfway through the game before I realized this, at which point I was saddled with the results of earlier decisions and couldn't reverse the mess I was in.  I really wish I'd had time to play another game, as I was just blown away by the elegance they've achieved.  Deciding how best to utilize those very limited assets will make or break the game for you more than any single attack.

-Charlie