In the first round, the opponent chose rock, which beat my scissors. There's a possibility they might stick with rock since it worked previously. Alternatively, they might anticipate that I'll choose rock (expecting them to choose rock again) and choose paper to counter. By choosing paper, I cover the case where they repeat rock and have a 33% chance in the case they switch to something else. Given we're early in the game (round 2 of 10), it's reasonable to counter their previous successful move while gathering more information about their pattern.