Work your way through a dungeon, fight a creature arbitrarily deemed to be a "boss" character, then watch a five minute cinematic that reveals a scant bit more of an overarching narrative. Repeat over and over until the narrative reaches its conclusion. Much like with my issues with RPG length, my beef with this element of traditional RPG design is not with the design itself. I have no problem with a story being revealed bit by bit as the player progresses through the game. Oftentimes, however, these poorly designed dungeons are full of uninspired "puzzles," wave after wave of generic baddies, and exist solely for the purpose of providing the player with something to do, a way to kill time so as to prevent the game from being little more than a third-rate CGI film. I'm not really sure who decided that this console-style approach to RPGs was "fun," but it's little more than dangling a carrot on a string in front of a mule to get him to do menial tasks. In this case, instead of plowing the fields, the menial task is more akin to that of exterminator: clear the dungeon of troublesome pests and be rewarded for the effort with a shiny bit of bland exposition.
3) Enemies that scale to your level
I am not limiting this problem merely to games such as Final Fantasy VIII or Oblivion, in which the enemies literally scale in power in accordance with your own characters' levels (though this is certainly problematic and absurd in its own right). Instead, I am speaking in more general terms about the gameplay balance face-saving convention of dispatching more and more powerful enemies as the game progresses. Routinely fighting rats and common thugs with 20 HP in the early stages of the game is one thing; routinely fighting against elite soldiers and mages that are just as powerful as your epic-level demigod of a character in the late stages of the game is totally unacceptable.
Only very special characters make it to the higher levels of experience. As one 2nd Edition Dungeons and Dragons supplement stated, a truly epic-level character is pretty much a one in a million individual. For every hired goon that you encounter in late-game random encounters to be of a similarly high level to that of your characters is borderline insulting. It cheapens the player's accomplishments, as well as reeks of developers taking the lazy approach to game balance. Epic-level characters should be doing epic-level things, not merely mowing down artificially-enhanced baddies in the same manner as they did in the game's early hours. Likewise, epic characters wield awesome power – it makes zero sense to deprive the player of the fruits of his or her accomplishments by making all of their opponents equally powerful (and thus immune or highly resistant to the new powers that the player has spent so much time to acquire).
To be fair, tabletop RPGs like D&D suffer from a similar problem, as they too tend to collapse at the higher levels of experience. This issue is not limited to CRPGs in any case, but it's much more apparent and bothersome in the videogame experience.