This concept is the mechanic of a game requesting the user to press the start button to continue (or to begin the game before the main menu screen), but will accept other methods of input. A common example is the game accepting the 'A' button (or the 'X' button on PlayStation consoles), even though the "press start button" graphic is displayed.
Theoretically, this concession is made by developers in order to make jumping into the game a faster and more streamlined process. Some games chain together single button presses on the menu. Killzone 2, for instance, highlights the Single Player and Continue Game options in successionn press X three times in quick succession and immediately direc on the menu. From the Press Start Button screen, players cat the game to start loading from the most recent save game. Indeed, players can also skip the opening cinematics by pressing the X button. Conceivably, button mashing X as soon as the game loads could have the player facing the loading screen in under twenty seconds. This is also the case for Modern Warfare 2, where hitting A on 360 or X on PS3 multiple times can bring the player into a lobby within seconds of putting the game in the system.