Space Seed - S1-E23
Other mistake: Spock calls for McGivers and Scotty to the transporter room. In the Transporter Room, Scotty is at the controls, then after he went to the Transporter pad, they used a stock shot of his hands working the controls.
Space Seed - S1-E23
Revealing mistake: During the fight sequence between Kirk and Khan in the engine room, you can see in some shots that it is not William Shatner and Ricardo Montalban fighting, but their stunt doubles.
Space Seed - S1-E23
Visible crew/equipment: When Khan hides behind the wall in the engine room before Kirk enters, a crew member walks in front of the stage light and you can see the shadow of his head passing across the floor.
Space Seed - S1-E23
Continuity mistake: As the away team observes Khan in the stasis chamber, McCoy holds his tricorder with both hands, but the next shot shows him holding it in one hand.
Space Seed - S1-E23
Continuity mistake: On the Botany Bay, McCoy is not holding his tricorder, but when the ship's lights activate, McCoy suddenly has his tricorder in his hands.
Space Seed - S1-E23
Continuity mistake: When Khan asks Kirk "How long?" Kirk's head is near Khan's with nobody behind his head, but the next long shot shows Scotty behind Khan.
Space Seed - S1-E23
Continuity mistake: Khan's hands switch positions several times on the table between quick cuts as he and Kirk talk.
Space Seed - S1-E23
Continuity mistake: At the compression chamber, the pressure meter goes from thirty to ten too quickly to be accurate between shots. After showing ten, the meter jumps back to twenty.
Space Seed - S1-E23
Revealing mistake: Just before Kirk and Khan fight in Engineering, Khan bends Kirk's phaser pistol in half, but the small hand phaser on top is still functional.
A Taste of Armageddon - S1-E24
Visible crew/equipment: When Mea 3 escorts Kirk and his landing party to Anan 7 and members of the High Council, while the group enters the room the actors' marks are visible on the black rug, as they all stand at their marks. (00:06:55)
A Taste of Armageddon - S1-E24
Continuity mistake: Just after the ship is first attacked, Scotty tells McCoy, "We can't fire full phasers with our screens up." Say what? The Enterprise couldn't operate transporters with the shields up, but it fired its phasers, full or otherwise, with the screens up every time it went into battle, and always had. If they'd been forced to shut their shields down every time they fired, the Enterprise would have been history long before this. (00:23:30)
A Taste of Armageddon - S1-E24
Continuity mistake: The landing party had been apprehended and placed in a locked room under the supervision of a single guard. Spock manages to free them and Kirk knocks out this guard, leaving him in the locked room. Later on in the episode, they return to this very room and somehow this guard is gone. He could not have woken up and walked out because it is a locked room and Kirk took his key. (00:23:45)
A Taste of Armageddon - S1-E24
Plot hole: The ambassador and his aide beam down to the planet. This would not be possible because earlier on Scotty refused to lower the screens/shields until the Captain told him to do so. It had already been established in an earlier episode titled "Arena" that transporters don't work with screens up. (00:32:40)
A Taste of Armageddon - S1-E24
Factual error: How do the Eminiarians fire a weapon based on sound ("Decibels - 18 to the 12th power") up into the vacuum of space at the Enterprise?
A Taste of Armageddon - S1-E24
Continuity mistake: At the end of the teaser, Kirk orders Yellow Alert, but the Red Alert alarm sounds.
A Taste of Armageddon - S1-E24
Continuity mistake: The chamber the guards try to shove Fox in is open when Spock shoos everyone away. But it's closed when he goes to blast it.
A Taste of Armageddon - S1-E24
Continuity mistake: At the door, as Spock gives Yeoman Tamura her orders, his hands are in front of him. In the close up, they are suddenly by his sides.
A Taste of Armageddon - S1-E24
Revealing mistake: It is easy to tell where the matte painting and live action area meet when Fox and the assistant appear.
This Side of Paradise - S1-E25
Continuity mistake: Kirk threw a "spore flower" across the bridge and it landed towards the front of the bridge. Later on, Kirk returns to the bridge and despite all the crew being on the planet the flower is gone. (00:28:20)
This Side of Paradise - S1-E25
Continuity mistake: As Spock beams up from the planet, Kirk, who is manning the transporter controls suddenly pulls a steel pipe from nowhere. (00:33:55)
Answer: After causing Norman to overload, all of the other androids shut down. The same could be said for the androids on the Enterprise.