# WorldOracle example: A seemingly successful robot rollout may predict the wrong grasp

- Source: Reddit r/robotics
- Published: 2026-10-31T06:40:15.000Z
- RoboHot: https://robohot.news/en/items/a7dr8lkp394jwnrfuybn4cmf5
- Original: https://www.reddit.com/r/robotics/comments/1xk34ea/a_convincing_robot_rollout_can_still_predict_the/

## Summary

WorldOracle presents a case where the real gripper failed to grasp the fruit, but the generated rollout showed the fruit being picked up, despite the model receiving the same initial observation and recorded actions. When evaluating predictions, check separately whether the robotic arm follows the trajectory and whether the object's final state is correct; for an empty grasp, predicting an empty grasp is the correct answer, while a seemingly successful grasp video may actually be wrong.