I would disagree since most jobs, especially DPS jobs, are all about learning your rotation/priority system. While dungeons are repetitive, they give you a lot of chances to learn a nice, fluid combo that works with the skills you have. Early dungeons? Not so much. Mid-late dungeons? I'd say so. Then again, this is up to the player in dungeons. If you want to learn to maximize your rotation to speed up the process, you can. If you wanna go through the motions and get through it, sure. In fates? You need to go through the motion or spam aoe just to get hate/damage and get max credit.
I guess I would argue that you have a better opportunity to learn your class by playing dungeons. The repeat pulls give you more and more chances to see how best to utilize your skillset. Problem is most people see them as chores instead of learning opportunities. Endgame dungeons don't have enough of that learning and reward system to justify repeat playthroughs, which is the biggest downfall of the level 50 dungeons. You literally only do them to get tomes to get gear, which is a pain and, ultimately, not rewarding enough for the time put in.
