Continuity mistake: A thief comes out of the Century Savings Bank, but the money bag he holds reads Metropolis Bank.
Continuity mistake: From the inside, the sign on Archibald Data Processing has a square thing on top of the first and last letters. From the outside it doesn't.
Continuity mistake: When the roller-skate girl grabs the trolley, the cups and food on the upper plate fall. A frame later they're all back on.
Continuity mistake: When the roller-skate girl grabs the trolley. In the close ups she is bending to the front, in the wide ones standing straight.
Continuity mistake: When the Pisa tower seller sees Superman, the wineskin swaps sides between shots.
Continuity mistake: When evil Superman crushes Clark's glasses, they swap around 180ยบ between shots.
Continuity mistake: The tornado in Colombia blows out some candles, but they all appear lit up again a shot later.
Continuity mistake: When Gus flies away with the skis, the sky keeps changing from cloudy to sunny all the time.
Continuity mistake: When Superman first pulls the stack down to use as a slide for the workers, the bottom where it came out of the roof was a dark color. When the people go to slide down, it's all silver colored.
Continuity mistake: After Gus unscrews the computer, the lights go off and Superman's corner becomes dark. From the opposite angle it's perfectly lit.
Continuity mistake: When Gus disconnects the computer Superman lies flat on the floor. A shot later his right shoulder is raised, and his body rests on his left side.
Continuity mistake: The shot outside of the bus where Jimmy and Clark are shows a woman and a man sitting on the front seats. In the shot inside the bus they disappear.
Continuity mistake: When Gus breaks the lattice in pieces and skis away, in the immediate wide angle all the falling wood and debris has disappeared.
Continuity mistake: After Clark kills the bad Superman, he has dishevelled hair but after he flies it's now perfectly combed again.
Continuity mistake: When Superman struggles to stop being dragged by the computer, there is debris all over the floor. When the computer explodes the debris disappears.
Continuity mistake: When Superman takes Clark's glasses, he folds one arm of the glasses in. A moment later, that arm is extended, and he folds both arms and crushes them.
Continuity mistake: When the toy penguin waddles into the smudge pot, its right wing and head catch fire. When Clark sees it, only a small amount of flame is on top of the head.
Continuity mistake: In the junkyard, when Clark comes out of the container, the hole he produces changes shape depending on the angle.
Continuity mistake: Evil Superman is chasing Clark on a conveyor belt and starts to shout and move swiftly as if he was flying. A frame later, from another angle, he is calmed, walking and repeating all previous movements.
Continuity mistake: When good Clark is on the trash compactor about to be covered in metal parts, he lays on a blue car hood. Depending on the angle the hood is barely rusty or very rusty.
Answer: There were rumors that Hackman was angry with the Salkind Brothers (the producers) for firing director Richard Donner, though Hackman later disputed saying that. His explanation, though he may have been downplaying the real reason, was that he had a number of other movie projects at the time, and he also did not wish to continually play the same villain in an ongoing movie series.
raywest ★