Video prompt: His eyes are focused intently on the dartboard hanging on the opposite wall, surrounded by colorful posters and trophies. With a determined expression, he takes a deep breath, raises his arm, and with a swift flick of his wrist, sends the first dart sailing through the air. It spins gracefully, cutting through the air with precision, before landing with a satisfying thud near the bullseye. Encouraged by his success, the boy grins widely, his eyes sparkling with excitement. He quickly readies another dart, adjusting his stance slightly, and throws again, each dart landing closer to the center. Around him, friends cheer and offer playful advice, their voices blending with the soft hum of a nearby arcade machine. The room is alive with energy, a testament to the joy of friendly competition.
Defect: unsmooth motion ( motion is correct)
Explanation: The dart seems to be on the dartboard at first, but then it shakes vigorously in the air until the boy grabs it. At that point, it seems to move weirdly and momentarily partially disappear.