I was playing Resident Evil 4 on the PS2 last night. It's a very graphically impressive game. However, it does have a major flaw (which it shares with most other games) - it's not always fun to play.
[Spoiler warning] If anyone out there has RE4, it's the bit where you have to fight the first giant/ogre thing (see right). It's one of those boss battles where you have to guess where the weak spot is, and also what else you have to do. If you don't work it out, you'll be stuck on the level forever, and the only way I can see of working it out is to spend a whole day on it, or look on the internet. In this case, you have to shoot it in the head until something bursts out of it's neck, and then run up to it and jump onto its back and stab this thing. You have to do this 3 times as well, so hopefully you won't run out of ammo.
The problem with the bit in question, as well as getting a bit tedious, was that it is preceeded by a 30-second movie clip that you can't skip through. Every time you die, you have to run back to the same point in the game, and then sit through the same clip again. Why do companies think that we want to watch the same clip over and over again? To massage their ego?
The various GTA (and a lot of other) games suffer from this problem as well. If you fail at a mission for example, you then have to go through the build-up to the mission all over again (reloading the game, running to that area of the map to get the mission, run to the area of the map where the mission takes place etc..). This wouldn't be a problem if these bits of the game were fun, but running across a map is rarely fun, especially the second (or third...) time round.
The bottom line is games should be fun. All the time.