Presentation affects perception affects enjoyment.
Guild Wars has 8 dungeon options. I have run them all. I am pretty much out of things to do rather than re-do, and do I really want to grind a dungeon 19 times to get an armor set?
Guild Wars has 33 dungeon options. Every dungeon has story mode plus three exploration paths (four in Arah). I have run 15 of those 33. I am less than half-way through. Most of the endgame lies before me, and having run all 8 story modes, it is all immediately accessible.
How you count matters. If you think of the three explorations as the same dungeon, doing all three in a night is a groan-worthy grind. If you think of the them as different dungeons, doing all three in a night is quite a varied experience. Some dungeons will lend themselves more and less to either interpretation; some have a choice of paths before you see the first enemy, while others have significant overlap.
The November monthly achievement set includes “run 5 dungeons.” Some forum-goers are up in arms about this. Do they really believe that of 33 dungeon options, they cannot find 1 or 2 worth running weekly? ArenaNet is batting 0 for 33? They more likely see 8 dungeons, all of which will have at least 1 problem on at least 1 path, so all the dungeons are borked. How you count matters.
I understand the angry soloers, but hey, you lose that argument. MMOs will have some achievements that encourage and reward group play. It’s kind of a thing, you know?