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.
In Tamagotchi! Yume Kira Dream episode 25, Mametchi tries to build a robot duplicate of Cafe Mama's husband for her birthday, complete with recorded dialog. While he's recording his voice, Patitchi overhears him and thinks Mametchi is confessing his love to her.
In the same episode, Kiraritchi doing the robot.
In Tamagotchi! Yume Kira Dream episode 26, while riding Himespetchi's ship, Pianitchi, Yumemitchi and Kiraritchi ask Mametchi to sing. Mametchi's singing is so awful that it crashes the ship.
Kuchipatchi fattening himself up into a ball in episode 1 of Go Go! Tamagotchi. His squeals of joy while rolling around are priceless.
Nightmare Retardant: When he does finally wake up, he resembles a giant space squid, and has an equally goofy voice.
That...awful robot husband Mametchi builds in Tamagotchi! Yume Kira Dream episode 25. Especially its crude face. Mametchi's friends are rightfully unnerved.
Player Punch: The death sequence on any Tamagotchi is drawn out to be as heartbreaking as possible. This is turned Up to Eleven on the Gameboy edition, where you're forced to watch your Tamagotchi's last moments while sad, solemn music plays.
Porting Disaster: The Tamagotchi L.I.F.E. apps are ports of the original virtual pets. While there are minor issues like the animations being off, the biggest issue is how the pets' growth patterns and conditions are altered or don't exist, meaning it's nearly impossible to get certain characters.
The Generation 2 update completely changes the mechanics of the Gen 2 game, adding the number 0 (originally it only allowed 1 through 9), letting the pet's second number sometimes be the same as the first, and the "next" number after a round is random instead of the last number they thought of.
The Angel app has the programming and sprites in place for using the Praise icon, but the pet never calls for it. Worse, there's much more leeway on raising it, so a player could obtain the best character with absolutely no effort, while getting anything less requires carefully balancing neglect and care, and some luck.
Scrappy Mechanic: The overall toy; many people have had less trouble taking care of a real animal than a Tamagotchi or anything similar.
Early on, the built-in clock. When the original toy launched in 1997, there was plenty of confusion as to what the clock was for. It was on the toy for two reasons: to give the Tamagotchi a practical value of being a watch, and to make sure the Tamagotchi woke and slept at regular hours. What happened instead was users put the clock to any time, causing the Tamagotchi to sleep during the day and wake up at night.
The Push Notifications for the iPhone edition quickly become this once the baby's born.
Everywhere in The Movie. First we have Mametchi breaking down to tears when he hears that the sun left Tamagotchi Planet because of him. Not much longer later, he falls into a black hole trying to save the planet, and he's TERRIFIED of the dark, followed by shots of the entire cast (including his little sister and family) watching on in horror. And we all knew that Tanpopo would go home at the end of the film, but we didn't expect Chamametchi bursting into tears, and the rest of the cast slowly following suit.
Tamagotchi! Yume Kira Dream episode 20 is full of this. Mametchi's still miserable after losing the competition in the last episode, and an argument with Ikaritchi prompts him to run away and find a new place to stay.
Even worse, he later visits Himespetchi and asks her to bring him back to Tamagotchi Town. After a fierce argument, Himespetchi throws Mametchi out of her ship before curling up on the floor and crying.
That One Level: Level 59 of Tap and Hatch. It can be completed without paying for power-ups, but it's an agonizing endeavour.
They Just Didn't Care: Bandai US's attempted revival, Tamatown Tama-Go, is this. With how little marketing Bandai did for the line, as well as how little product has been released, one must wonder if Bandai US even wanted to keep the franchise going.
They Wasted a Perfectly Good Plot: The iD L 15th Anniversary Version in Japan. It was meant to be a celebration of Tamagotchi toys for the past fifteen years...except Bandai put the character roster up as a poll on the site, where people could vote on which adult characters they wanted. As much of the original audience in Japan was gone and replaced with those who know Tamagotchi primarily from the anime adaption, the end result was only five vintage adult characters making the cut (out of 32 total adult characters), while the rest of the cast comprised of characters made popular by the anime.
Ugly Cute: Many of the characters obtained from neglect have a sort of charm all their own.