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.
YMMV: Plants vs. Zombies
Complacent Gaming Syndrome: Some players have pointed out that many plants are not very good except for a small handful, like Gloom Shrooms, Tall-Nuts, Cob Cannons, Blovers, and a small number of others, considering the mere amount of strategies that could be used to play this.
This often comes more from those who've scored over 150 flags in Survival Endless as to standard play, in which they find a specific strategy and stick with it.
Averted in the New Game Plus, where Crazy Dave will pick 3 plants at random that you have to use.
Giga-Gargantaurs are even worse. They take significantly more to kill, and have crazed red eyes. Notably, they were put into Survival: Endless because the regular ones were too easy for early play.
The Jack-in-the-Box Zombie can instantly destroy your defenses.
Zombonis. They cannot be slowed by Snow Peas and Wintermelons, nor can they be stopped by Ice-shrooms or Kernel-pults' butter. They squash all your plants in the way and they are freaking fast! To top it off. They leave unplantable ice trail that needs to be melted with a jalapeno and said ice trail causes bobsled zombies to appear. Thankfully, Spikeweed and Spikerocks will finish them off in one hit should they run over one. And the ice disappears after a short period.
In "I, Zombie", Magnet-shrooms. They take away bucket heads, mining picks, ladders and football helmets, making many of your tougher and more expensive zombies get easily decimated. Starfruit and Threepeaters can attack other columns/rows, providing extra firepower and easily screwing up your imps should you choose to send them down a (seemingly) harmless row.
Kernel-pults, due to their random chance of throwing butter that stuns your zombies, can become these should the Random Number God choose to be nasty and cause them to constantly chuck butter. Coupled with snow peas that slow your zombies from reaching them, and you may have a nightmare on your hands.
Pole-Volt and Dolphin-Rider Zombie can be EXTREMELY infuriating. The abilities render defensive plants like Wall-Nut and Garlic useless. Take this advice, Tall-Nut is your friend.
For that matter, why do long-submerged, coral-covered zombies keep coming out of my swimming pool?
How about Disco Zombie's backup dancers? More and more backup dancers keep rising from the ground. Just how many dancers have been buried in the front yard?
"Funny Aneurysm" Moment: The game was released in 2009. The Dancing Zombie originally looked like Michael Jackson. Six months after the game was released, the King of Pop died of cardiac arrest. Whoops. They ended up fixing this in a patch.
Game Breaker: In the flash version's survival, the Fume-shroom and Sun-shroom combo becomes this at night. Sprinkle the cake with Grave Busters and Wall-nuts for success and profit.
Cattails in any pool stage.
The Gloom-shroom/Garlic combo. The garlic diverts the zombies down to other lanes and clustered up together so that the Gloom-shroom can blast them. This can eliminate at least of 75% of the zombies types in the almanac. Unfortunately, they don't stop Zombonis and Gargantuar, so keep some one-hitters and a front row of Spikerocks as buffer.
The Spikeweed/Wall Nut combo. The zombies are kept on the spikeweed by the wall-nut, and the spikeweed destroys them with minimal losses.
Using the Hypno-shroom on any sufficiently powerful zombie. The Football Zombie is the most tempting target, though the Dancing Zombie is even better, with the back-up dancers also turned around. And the Jack-in-the-Box Zombie would mean no longer any risk of blasting your plants, and one free explosion against the other zombies if you're lucky.
Cob Cannons in Survival: Endless. With enough of them to continuously fire at regular intervals, one can go on indefinitely. Due to this, a cobless setup is a popular Self-Imposed Challenge.
Goddamned Bats: The Bungee zombie drops down and randomly steals one of your plants.
Balloon Zombies, unless you planted a Cattail or put a Cactus in each lane. Otherwise, you have to plant lots of Blovers every time one shows up, or it'll float right over every defense you have. They're easy to stop, but when you're trying to get enough sun for something fairly expensive, it can get REALLY frustrating to have to keep using up 100 sun to stop them.
In the puzzle mini-game "I, Zombie" where you play as the zombies, the snow peas and kernel-pults are these. The snow peas slow down your zombies, and the kernel-pults will randomly stun them with a block of butter. Heaven help you if a kernel-pult and snow pea are in the same row, slowing and stunning your football zombie. While he's on a bed of spikeweeds.
Also, one of the "Brainssss..." sound sample, specifically the one said in a low creepy voice. The other samples, however...
"A huge wave of zombies is approaching... "
Nightmare Retardant: The other "Brainsss?" and short "Brains!" sound samples, which are said at a notably higher pitched voice. It sounded narmish instead, like it was said by someone who got clubbed in the head shortly prior.
"Stop Having Fun" Guys: Mostly more from the people who've scored over 100+ on endless survival and have used specific plants tend to think that everyone else should play it according to specific strategies they used.
Squick: Brain controlled zombies turn around and eat their fellow zombies.
That One Attack: The Zomboss battle can be summed up in four words: WINNEBAGO ATTACK FREAKING SUCKS!
Although the attack is predictable (immediately after getting back up, less than half his max hp left), there's absolutely nothing you can do to stop it from insta-killing 6 of your plants.
Stage 4-10. The stage is in complete darkness which you cannot see your plants or the incoming zombies until lightning illuminates the lawn for a few seconds. It is also a conveyor level. You'll get to unlock the Yeti Zombie the second time you play it though.
Same thing for level 5-5, which is where you're fighting against oncoming waves of bungee zombies relying on nothing but Chompers, Pumpkins, Flower Pots, and Cherry Bombs. Crazy Dave sums it up at the start of the level.
Crazy Dave: You're gonna hate this level. It's one bungee zombie after another. I hate those bungee zombies. With a passion. And a vengeance. Here come those idiots now.
The "Survival - Fog (Hard)" level. "Hard" is a MASSIVE understatement. The fog levels are among the hardest in the game to begin with, but this one takes it Up to Eleven and beyond. If you pick your nighttime plants well, you can actually get fairly smoothly through the first six flags... but then the game will (as in, 100% guarantee — it's part of the level design!) send a few Gargantuars your way for flags 7 and 8, who will not hesitate to flatten your entire carefully-prepared yard without blinking an eye. The final waves become largely a Luck-Based Mission based on how many of of your plants are alive.
"Column Like You See 'Em" and "Bobsled Bonanza" are two difficult mini-games that mostly rely on luck. The former gives you plants on a conveyor belt, and will only give you Flower Pots and Pumpkins right when the waves of Gargantuars start swarming you. The latter can ruin you by sending you several bobsled teams before you set up anything that can kill them. The former overlaps with That One Achievement when attempting to beat it without using Jalapenos.
The Woobie: The Wall-Nut starts off looking more than happy to protect the lives of its planter and comrades, but when the zombies begin to devour him and his smiles slowly disappears, you can't help but feel sorry for him.
A single tear begins to stream down Tall-Nut's face when he gets near the end of his health. Apparently the game's composer and a few beta testers would protect Tall-Nut with a Pumpkin because the tear made them feel bad for poor Tall-Nut.
Although the Tall-Nut tear is more of a manly tear.
The Garlic starts off looking happy and care-free, but when he's near the end of his health, he gets big tear-filled eyes...