I'm placing my "X" in the top-middle position (0,1) to create a winning threat in the middle column. I already have an "X" in the middle (1,1), so this move creates a potential winning line. If my opponent doesn't block at (2,1) on their next turn, I can win by completing the middle column. While there's no guaranteed win at this point, this move applies the most pressure and creates the clearest path to a potential victory.