draw after 3 repetitive moves


i guess i don't understand the draw. i moved the same pieces, repeating the move three times. why don't i get a draw for this?
http://www.chess.com/learn-how-to-play-chess.html#draws
"A player declares a draw if the same exact position is repeated three times (though not necessarily three times in a row)".
Repetition of position includes your opponent's pieces. Castling and en passant must be the same as well.