Jak 3

On the surface, this game is a straight upgrade to Jak II. More weapons, more powers, more vehicles. Weapons like the Plasmite RPG and Beam Reflexor are just plain fun to play around with, and the Light Jak powers keep the frustration level down in the main gameplay segments. The Jetboard has improved controls, as well.

Jak 3's opening is paced very poorly from a gameplay perspective. After the intro on-foot tutorial, you are treated to a leaper lizard tutorial, a button-pressing minigame, a buggy tutorial, a buggy race, another buggy race, a leaper lizard race, and a buggy combat segment. There really should have been an on-foot mission thrown in there to break it up.
The start of the second act is similarly paced poorly. Jak gets out of the catacombs deep under the city, and is immediately told to go through the sewers. Once he emerges in the port, he does four more missions before being told to go into the sewers again. It's already lame that the "big return" to Haven City is a return to the most ruined part of the city, where all there is to do is trek through the sewers. It's even worse that you have to return to the sewers again so soon.

The pacing is by no means the worst problem with this game, however. The big problem is not exclusive to this one game, but is present in many, many games from this era. Toward the middle of the PS2's lifespan, after the huge success of GTA3, it was decided somewhere that games could not be just "one thing" any more. Games included many different gameplay styles and minigames that were far different than the rest of the game. Sometimes, you'd find that these gameplay styles meshed and complimented eachother well, but in a lot of others, they just wouldn't. You'd have some arbitrary minigame that's way too hard, not fun to play, and required to progress to what you actually want to be doing.

Jak 3 loves these minigames. Some are quick and painless, like the "press the buttons as the icon passes through the circle" minigame. Two of them, however, stick out in my mind as absolute roadblocks that have stalled out multiple playthroughs for me. I've beaten this game a few times, but many more times, I just give up at one of these two minigames.
The first is a Pacman clone, where you have to collect all the pellets while a single "ghost" roams around in an expanding and shrinking circle. There's also another robot thing that will appear to create more pellets occasionally. It sounds simple, but it's absolutely maddening how many times I've almost beaten it and been eaten by the ghost and had to start completely over. It's a much harder game than it sounds, unless you're Billy Mitchell.
The second is a turret minigame. If there's one thing I hate in videogames, it's turret minigames. Shoot the boss, he launches missiles at you, which you have to shoot, or you'll die. They take fucking forever and they are not fun in the slightest. If you get even slightly impatient, you die and have to start the hour-long minigame all over again. Fucking hooray.
The difference between these minigames and other hard missions is that these minigames don't use the skills you've gained and honed over the course of the game. They come out of left field and force you to learn an entirely new skill for no reason. If I wanted to play Pacman, I'd play fucking Pacman. I'm playing Jak 3 because I want to jump around, shoot guns, and drive buggies. Having a hard, required minigame that requires a completely new skillset pop up out of the blue is the worst thing you can do as a game designer.