I'm placing my O in the top-left corner (0,0) for several strategic reasons. First, since I already control the center (1,1), this creates a potential diagonal winning path from top-left to bottom-right. My opponent has placed Xs in the middle column (0,1 and 2,1), so taking this corner prevents them from developing a fork. This move gives me two potential winning paths - either completing the diagonal through position 2,2 or potentially creating a horizontal line across the middle row if I can later secure position 1,0. Taking a corner when I already have the center is a strong positional play in Tic-Tac-Toe.