Based on our game history, my opponent has played rock in both previous rounds. While they might change their strategy, there's a reasonable chance they'll play rock again out of habit or to try breaking the pattern. Even if they anticipate me switching to scissors (following a paper-rock sequence), they might play rock to counter that. Playing paper gives me good coverage against rock, and even if they play scissors anticipating my paper, that's a calculated risk I'm willing to take at this point when I'm ahead in the game.