These are what we call the 'YMMV items.' Things that some people find in this work. We call them 'your mileage might vary' because not everyone sees these things in the same way. This starts discussions in the trope lists, a thing we don't want. Please use the discussion page if you'd like to discuss any of these items.
Jason, in a couple of ways. He acts like a child much younger than ten, but the reasons for that are never mentioned; does he have a developmental disorder? Ordinary immaturity? Or just a plain, poorly-written kid?
Big Lipped Alligator Moment: Madison's dream. The cause for it is never explained, but it does drive the story: Madison, too stressed to sleep in her own place, checks into a motel and meets Ethan.
The cause for Madison's insomnia is explained in scenes that didn't make the final cut of the game; she was a reporter during the Iraq war, and the horrors that she saw sparked her terrifying nightmares.
Dr. Adrian Baker murders people by surgery while they are still alive and conscious for no other motivation than his own enjoyment. He attempts to do this on Madison Page, and a Jehovah's witness because the man wouldn't stop pestering him. He isn't exactly averse to a spot of Cold-Blooded Torture before he kills his victims: with Madison, he acts friendly enough, but when she's in his clutches he begins attempting to torture her with a power drill.
Leland White, The Taxidermist in the DLC of the same name kills young women before stuffing them and displaying them around his house. If Madison attracts his attention during her escape he shows pure sadistic glee in hunting her down while taunting her about how he’s going to add her to his collection. When Madison first uncovers the inside of his home, she's rightly horrified to discover just how many women he's murdered and made part of sick little tableaus.
Counterpart Comparison: Jayden appears to be like Carla Valenti from Fahrenheit as both of them are investigators who are addicted to their jobs that they can't get any sleep and don't have a love life.
Madison is also very similar to Carla, as they both investigate the big crimes in their games, have some form of insomnia, and sleep with the main suspect of said crime.
Magnificent Bastard: The Origami Killer aka, Scott Shelby. Not only does he pretend to sympathize with the families of the victims, he succeeds in convincing everyone, including the player, he's out to save the day.
And him actually having Lauren fall for him for his supposed determination in finding her son's killer, while he himself was the one who committed the deed.
Moral Event Horizon: The Origami Killer may have an understandable motivation, and has grown up with a troubled past. But at the end, when Ethan has succeeded in all his trials and found his son, and it appears that Shelby intends on shooting him and leaving Shaun to die anyway, all bets are off.
The above is one possible scenario. In another, Scott allows Ethan to save his son and offers to let himself be shot.
His manipulation of Lauren certainly counts.
Lauren: "You killed my son, Scott. Were you thinking about that when you held me in your arms?"
Lt. Blake has two moments: beating Ethan up to know if he's the Origami Killer, and ordering his death.
Kramer wanting to protect his son at any cost may be somewhat understandable; his completely unwarranted comments about Lauren (if she died) being a whore and the victim being "street trash" (said just as Shelby is walking away) almost seem designed as an invocation of this trope.
Gordi Kramer's accent: "I'm the ARIGARMI Killer". Way to turn a tense, dramatic moment into LOL WUT
Blake getting mad at Norman: "fuckinAAASSHOOOLE!!"
The above "SHAAAUUUN" glitch in Good Bad Bugs can turn the entire warehouse scene into a truckload of narm.
The entire market chase. From the amount of ways to fail to some of Miroslav Corda's methods to get away, such as knocking down store things like a child to releasing chickens to bother Norman. Norman adds to the Narm by being annoyed by the chickens.
"OriGAMMY". See the Gordi Kramer example, but other characters are certainly capable of doing it, as well.
Never Live It Down: The diaper-changing minigame is a rather smaller deal than it's sometimes made out to be.
Player Punch: Goddammit, why did Shelby have to be the Origami Killer?
Depending on your actions, there could be several more. Made worse by the fact they're probably all your fault!
Grace is universally detested by players of the game on the grounds of her unreasonable action of divorcing Ethan for simply putting his life on the line to save his son from a car and thereby claiming virtually everything he owns save for full custody of Shaun. Needless to say, some feel they wish she fell victim to the killer herself.
There's also the fact she assumes Ethan is the Origami killer for practically no reason.
Forget the fact he's a kid, Jason certainly doesn't seem to be too bright. How many kids do you know that would go wandering off in a crowded mall for no reason, and then try to cross the street while a car's coming, thus making him Too Dumb to Live? Yeah, Jason is not a bright kid at all, and players certainly don't think fondly of him.
Adding to that is the fact that Jason wanders off twice in the mall, and the second time comes after his father explicitly warns him not to do it again.
So does that make him a case of Alas, Poor Scrappy immediately into the game and despite being the protagonist's prepubescent son?
Depends on whether or not you actually feel bad that Jason dies, rather than just feeling bad for the Mars family coping with losing him. On the one hand, it's sad that a child was killed in a senseless accident, but on the other hand, Jason is a proud winner of the Darwin Award.
Shocking Swerve: Shelby being the Oragami Killer. On your first playthrough, you're almost certainly not playing him as though he is, making several of his actions rather odd.
When Jayden investigates the scene at the nightclub, one of his thoughts just emphasizes his woobieness:
Jayden: I am sick and tired of getting the shit kicked out of me on this investigation!
There's also Lauren, a mother mourning the loss of her only child. And there really is no happy ending in store for her: she either dies over the course of the game, or survives only to find out that the sweet private detective she's grown attached to while trying to track down her son's killer together is actually the killer in question. Ouch.
Lauren does get a somewhat positive ending, where she kills the Origami Killer herself to exact her revenge.