Audio/visual unsynchronized: When Sgt. Ramsay goes in to rescue the baby, the rogue robot is heard to cock a shotgun several times before firing its weapon. The weapon, however, is a revolver and could not possibly produce the sound we hear.
Miscellaneous: When Ramsey goes into the house to rescue the infant from the killer robot, he steps on the mini bush, the supposedly real plant is obviously a fake.
Crew or equipment visible: Reflection of steady cam and operator on the Coke truck during the alley chase scene.
Revealing mistakes: During the car chase scene, a few shots show strings attached to the little robots.
Factual errors: When Ramsay goes to rescue the child, a total of eight shots are fired by the robot from a 357 magnum handgun. This type gun is designed in five and six shot models only. There is no such thing as an eight shot 357 magnum.
Miscellaneous: When Ramsay watches Miss Rogers on the monitor as she is cornered by the sentry robot, she reacts to a Taser hit, but the arc isn't there. The optical effect is missing.
Plot holes: Officer Thompson has a scene wherein she describes Luther to an officer, who creates a computerized image of him using a handheld device. Why bother when they've already got his image on the tape from Johnson's door monitor?