Well that's just it Joe. You still level to end game. You LEVEL to end game in every game.
The question there is, depending on the game, what you can do "at" end game and wether such content is Tiered all on its own.
In Istaria, endgame is one "tier" so to speak. You get to 100 as a dragon, (or whatever it is when you're done multiclassing as a biped lol) and you are at end game. Your endgame then is either - building hoarde, crafting, or killing the same monsters repeatedly for personal reasons =D.
Wheras in EQII or WOW the endgame is literally the beginnign of another game. The endgame-game
. You start in on dungeons, and then once you have enough gear, you then move on to raids. ANd there are levels of raids. You have to do level 1 of raids to get to level 2 of raids (different places to run) to get to level 3 of raids and so on. This way you have the option of either staying at any level (you can stop at level 1 and never go anywhere else), or you can keep "leveling" so to speak through more content.
Istaria just has the "level 1" and once you've done it all once - you've literally "beaten" the game so to speak. Its only those who are interested in crafting, title building, helping friends out forever, or alts that will continue to engage themselves in the game.
Whereas most other gamers, having not grown up on such a system - are expecting max level to just open up a whole bunch of more content. The idea that "the fun starts at end game" can be true for some people, and for some games. I personally have fun the whole journey or I never get to end game but that's me (and that's in WoW, Istaria, LOTR, EQII, AoC, WAR, Rift, all of them forever..)
I don't see either system as better or worse than another. Just different *shrugs* I personally prefer the idea that hitting end game doesn't mean "run out" of content (the way I feel Istaria hits a wall there), and I like the idea of greater tiers of content beyond "max level" simply because it gives me more stuff to do even if I'm at level 100 and it gives me new things to explore and learn about.
But again, that's me.