Continuity mistake: We first see from the inside of the door (and therefore backwards) the instructions that Mr. Miyagi leaves for Daniel to paint the house. In the next shot we see the same note from the outside - from Daniel's viewpoint. Clearly they are two different notes. The left & right arrows switch directions, the drawings of the hands change, the position of Miyagi's signature changes, and the placement of some of the exclamation points changes.
Other mistake: Mace's reflection can still be seen on the pond after he disappears. (00:53:30)
Suggested correction: This isn't a mistake. That's him, under the water in the same pose he was in before he touched the water.
After watching the scene, the mistake is valid. When he's underwater, he's not in the same "pose." That would require him to be upside down and squatting. But that's not the pose we see him in.
Bishop73
We see Mace semi-kneeling and reaching out to touch the water when he vanishes, but his upside-down reflection is still in the exact same calm position even when he's gone, and in the next shot we see Mace under the water right-side up, with his arms reaching up to the surface. This is a valid mistake, the suggested correction is not right.
Super Grover ★