Playing Rock Paper Scissors against a mirror is good for self-examination. Playing against a random number generator is good for calibration. Playing against a computer opponent that actually tracks your pattern history is good for the same reason that hitting off a pitching machine is good: the feedback is immediate, the opponent is tireless, and the data is honest.
The WRPSA's Rock Paper Scissors app plays against your behavioral tendencies. It tracks which gestures you lean on under pressure, identifies your win-stay lose-shift patterns, and makes predictions that get sharper as the match runs longer. Early in a session, you're close to even. Deeper in a session, you're fighting your own history.
This is the most efficient way to diagnose what you're doing wrong without needing another person to do it with. Most players know their obvious tells. The ones that cost you in competitive play are the ones you can't see because they're embedded in your automatic responses. The app surfaces them.
Download it, lose to it a few times, and pay attention to the rounds you lose. The app isn't winning because it's randomizing. It's winning because it's reading you.