Continuity mistake: Throughout the film the size of the Iron Giant varies from being able to hide in a barn shed to sticking out well above a town to be spotted from a fair distance. A good example is when the Iron Giant launches himself after a fall from a cliff in front of Hogarth's mother.
The Iron Giant (1999)
Plot summary
Directed by: Brad Bird
Starring: Jennifer Aniston, Vin Diesel, Harry Connick Jr., James Gammon
Hogarth Hughes is a 9-year-old boy living in Rockwell, Maine in 1957. One night, while home alone, a large object comes crashing down from the sky and lands behind his house. He goes to investigate, and comes across a robotic giant feeding on the metal in a power plant. Hogarth is chased away by the strange machine, but returns and meets up with him again the next morning. The giant begins to follow him home, and Hogarth eventually allows him to live in the shed behind his house. Hogarth befriends the giant and the giant begins to speak and even learn. However, Kent Mansley, a government agent, sees the giant as a threat to the country, and isn't about to let him get away...
More mistakes in The Iron Giant
Kent Mansley: Launch the missile now.
Trivia: The Iron Giant has only 53 words of dialogue in the entire film.
Answer: It was a laxative to make him go to the bathroom.