Stupidity: The Tomorrow People tend to enjoy walking into and walking out of most scenes rather than teleporting. In particular, when fighting and needing to run away, they'll teleport to get a better fighting vantage instead of teleporting out of the situation.
Who, What, Where, Wendigo? - S2-E10
Stupidity: Dwight, Audrey, and Nathan all know Dwight's trouble is that all bullets are attracted to him, so why is he with them when they go looking for the killer, knowing every one is using a gun?
Welcome to Hotel del Luna - S1-E1
Stupidity: The Mayor realises that Man-wol has approached him and taken out her rifle to shoot him with. Yet during the entire time she takes to aim the rifle at him and fire, the Mayor makes no attempt to flee the stage for his own protection. (00:38:15)
Stupidity: Why does Jack Cassidy plant the lighter in the office when he could just pretend he has forgotten it? Does not make sense.
Stupidity: "Rei" comes into the circle, having been champing at the bit to "turn him into a smear on the floor." She's wielding a sword, Kovacs is unarmed, and she...slices him a bit, instead of a quick killing blow.
Worlds Apart - S1-E2
Stupidity: The bad guy kills the deputy in the swamp, then later sees a little girl who witnesses the killing run away. He then searches the boat for a weapon and runs off after her after he finds a machete, without even considering the officer's gun still in its holster. Abby proceeds to make the exact same mistake later when she finds the dead officer (meaning there's danger nearby) and hears the girl screaming and runs in the direction of the screaming without taking the gun to protect herself.
Stupidity: S50: Starting in episode 120 Genoa City had a celebratory gala at the GCAC. After the gala everyone that was staying long-term at the Grand Phoenix Hotel is now staying at the GCAC. The GCAC long-term rates must be much better to make everyone move out of the Grand Phoenix.
The Night of the Firebrand - S3-E2
Stupidity: West is introduced to, then knocked unconscious by Vixen as she hides a club behind her back. A trained Secret Service agent like West would not have let his guard down in this situation, as the entire fort was awash in bad guys.
Stupidity: Why do they always have to go through that washing machine setup in the laundromat when they have a great functioning elevator to the lab?
Suggested correction: Why would Gus go through the process of hiding the lab entrance stairs behind a washing machine but leave access to a freight elevator wide open? The elevator would be just as hidden and probably locked up. Not to mention it would be slower to take than simply walking downstairs.
When in Rome - S1-E3
Stupidity: A supposedly covert camera is placed in plain sight on a wall in a crowded room, with a prominent antenna showing, and a blinking blue light. (00:16:55)
Stupidity: While discussing his arrest with Emily, Seth mentions that he didn't tell the arresting officer that he works for Kirkman. As the White House's liaison to the media, Seth has a high degree of visibility; it would extremely difficult, if not downright impossible, to keep his place of employment concealed from the police for very long in the time between his booking and arraignment and when Kendra bails him out the following day.
Backlash of the Hunter - S1-E1
Stupidity: Rockford knows almost nothing about the guy who is tailing him except that he noticed him while he was grabbing a bite with his client. Regardless of that, he sends the same client to seduce him, just assuming that he won't be able to recognize her. And it works. Is Lindsay Wagner this hard to forget, that this guy just an hour or two later isn't able to tell it's the same woman his target was meeting?
Day 4: 12:00 A.M.-1:00 A.M. - S4-E18
Stupidity: After leaving the power plant to pursue the terrorists and retrieve the nuclear football, Jack orders the helicopter to take out the first Jeep. After he realises parts of the football are missing, why does he not order the helicopter to pursue and take out the other Jeep, preventing any further trouble from Marwan? (End of season 4's story, most likely).
Stupidity: After Bernie discovers a treatment for the infection, radiotherapy, everything goes back to normal. Except the contagion is airborne (which is why they were going to flush the entire ship's atmosphere), so they're just going to re-infect themselves in a few hours. And there's only one room on the ship that can be exposed to stellar radiation, so there's no way to clean the atmosphere either.
Episode #1.8 - S1-E8
Stupidity: There's a gunman that just opened the school doors, and he's looking at the police like "a deer caught in the headlights" and they are all pointing their weapons at him and he's holding a gun mind you, but somehow these cops let him run back into the school without even taking a singe shot at him. His background was clear too, so if the cops fired there would've been no collateral damage if they had a shoot out. (00:35:00 - 00:35:30)
Episode #1.2 - S1-E2
Stupidity: The part when the Colonel and the governess pose as journalists does not make sense. It's far-fetched enough that after a lengthy interview about the culprit's fortune the topic of his family never came up, considering it was one of the main goals and an ideal question to lead with, but considering that "mr. Todo" does not want a picture taken and has a tight security, there's no way that a photographer carrying a large 1930 camera would have been allowed into the interview room to begin with.
The Power of the Doctor - S13-E9
Stupidity: After the crew of the space train have taken out the Cybermen, the Cybermen begin regenerating, which one of the crew points out. This guy seems to be aware of how regeneration works, but doesn't shoot at them again. In the series, it has been shown that shooting someone during a regeneration cycle will kill them instantly, but this idea is never considered.
Stupidity: When they are conferring before surgery everyone is keeping scrub except for Avery who has his arms crossed. Shortly afterwards you can see him look around at all his co-stars, realise he screwed up and try to casually raise his arms. (00:15:00)