I see plenty of articles about the Free to Play versus Subscription argument when it comes to Eastern vs Western MMORPGs, but I'd like to step away from the revenue model and look at game design itself (as much as I actually can, given how closely tied revenue model is to game design). One of the major differences I've noticed between Eastern and Western MMORPGs are the differences in slowing progress through either "grind" or "luck" mechanics.
Grind: By grind, I refer to a game system that takes a long time, but is relatively predictable. An example of grind is leveling a character by killing monsters that give a fixed amount of XP per kill. If it takes 10,000 XP to level up, and a monster gives 100 XP, then every player that kills 100 of these monsters will go up a level.
Luck: By luck, I refer to a game system that is highly unpredictable. An example of luck would be weapon improvement common in many Eastern-designed games, where you have a chance to either get a better weapon or a worse weapon (or lose the weapon entirely). Each step has a lower chance of success, so getting the best weapon requires very many attempts (or tremendous luck) in order to pass all the levels. Some players might get it right away, some players might get it in a very long time, and some players might never get it, no matter how hard they try.
Luck-ish Grind: I'd also like to mention that there is a bit of a cross-over between luck and grind, especially in Western MMORPGs. For example, in World of Warcraft, leveling up trade skills has a certain degree of luck (each time you craft something, you may or may not get a point), but the luck element seems, by and large, marginalized by the generally predicable leveling slope from sufficiently high odds (IE: it might take 10 to 30 crafts to get 10 skill points, but it generally won't take more than that).
Western MMORPGs Reducing Luck
I think a great place to start this discussion is to see how Western games are trying to eliminate or reduce luck. World of Warcraft makes a fantastic case study becuase of their agressive luck-elimination program. In "Vanilla" WoW, loot drops in raids would consist of a few items from relatively large loot tables, such as a piece of armor for a specific class (eg: hunter helmet, mage gloves, etc.). In Burning Crusade, this system was replaced by a "token" drop system, where one of three tokens would drop for a specific piece of armor, which in turn could be traded for one of three or four armor pieces (eg: hunter/warrior/druid helmet, warlock/priest/shaman gloves, etc.). Then, in Wrath of the Lich King, the token system was further refined to eliminate the armor piece from the token, so there was only the three tokens and players could pick the piece of armor when turning it in (eg: hunter/warrior/druid token, etc.).
The reason for these changes were basically to reduce the luck needed to complete a set of armor and to reduce the wasted items that were not needed by the current raid composition. The end result was to reduce 50 pieces of loot (5 pieces, 10 classes) in Vanilla, to 15 pieces (5 pieces, 3 tokens) in BC, to 3 pieces of loot (just the 3 tokens).
Loot drops, however, were pretty much the only luck-based progression system in World of Warcraft. Crafting is limited by a luck-ish grind, because rare materials may be luck-based (you may or may not find the node you need, or get the resource you need when you harvest it) but harvesting has sufficiently high odds that all raw materials needed are sufficiently common to not be a strong luck-based limiting factor. More importantly, when crafting in World of Warcraft, you ALWAYS get the exact product you expect to get when you start.
Eastern MMORPGs and Lucky (or Unlucky) Progress
In stark contrast to World of Warcraft's reliable crafting, consider the crafting system in Final Fantasy XI, which has a luck-based chance of losing some of the resources put into the recipe, but more importantly a luck-based chance of the product being of different grades. When crafting a weapon, you have 4 basic categories of outcomes: you fail and lose materials (including potentially difficult to obtain and expensive materials, essentially causing you to lose all the work put into obtaining them), you fail but lose nothing (so you can try again!), you succeed and get a common result (which may not be the result you wanted...), or you succeed and get a high-quality result. For many items, players expect to get the high-quality result, and the common result may not even be worth much or anything at all.
This crafting system, over sufficient iterations, becomes more of a lucky-grind, though the iterations can be incredibly time-consuming when one of the materials you need to craft the item are a slim drop from a rare monster that might spawn once a week, assuming you actually tag the monster. The incredibly slim odds create rarity of certain crafted items, thus increasing their value.
A different progression system that I mentioned earlier exists in many Estern MMORPGs, and that's the "weapon upgrade" system. The basic principle is that each weapon has "levels" and must be "upgraded" to get from one level to the next. However, when you try to upgrade the weapon, there are four possible outcomes (depending on the game): you fail and lose the weapon entirely, you fail and the weapon loses a level, you fail and the weapon stays the same, or you succeed and the weapon goes up a level.
In Phantasy Star Universe, the grind system allowed weapons to go from plain items (+0) to level 10 (+10). Originally, when you failed a level attempt the item would be lost entirely. However, in a later patch, the item would go back to +0 on a fail and the maximum you could upgrade a weapon would go down by one. Thus, the only way to get a +10 weapon would be to apply 10 consecutive successful upgrades and never ever fail on that weapon. Suffice it to say, the rarity of +10 items was extreme.
Cultural Influences on Luck vs Grind?
Could you immagine how upset a WoW player would be if they had to upgrade their Shadowmourne 10 times during the upgrade process from Epic to Legendary, and each time they had an increasing chance of losing the weapon entirely, with the final step leaving them with a slim (1%?) chance of actually succeeding? Yet this very luck-based system is common in Eastern MMORPGs, even applied to already extremely difficult to obtain items.
I'm no expert on sociology, however I'm going to go out on a limb and cast some wide generalizations on the East vs West cultural divide. It seems to me that an underlying philosophy in the West is one of merit: that "everyone" can do "anything" if they work hard at it. Of course, we all accept that this isn't entirely true: a person born blind will probably never be a military airfighter pilot. However, we in the west have put significant effort into ensuring that as many people can do as much as possible; most importantly, we have worked to eliminate artificial boundaries, such as race, class, gender, etc. in access to careers, activities, areas, and so forth. In the West we embrace the philosophy that if you want something that you can actually get, you can get it if you work hard enough.
Though I know relatively little about Eastern culture, I'm under the impression that they don't have the same sort of merit-based system we've adopted in the west. Most crucially, they don't have the same sense that hard work directly leads to achiving goals; rather, things like fate, destiny, and luck have a far greater impact on the outcome of each life. I reiterate, of course, that this is not a great understanding of Eastern culture, and I'd be grateful of another Gamasutra member could reply in the comments with more information about this.
However, this interpretation of cultural differences does seem to translate into the differences in game design: Western MMORPGs epitomize the ideal of merit, employing game systems that ensure that everyone can accomplish everything available if they put in enough hours grinding away; Eastern MMORPGs epitomize the ideal of luck, employing game systems that exaggerate luck-based success, ensuring that it is luck, not hard work, that leads to the greatest power.
What Does This Mean for F2P?
I want to tag on one last bit to this story: and that comes to localizing Eastern-designed F2P games for Western markets. It strikes me that it might be necessary to re-design many of the luck-based game systems into grind-based systems to appeal to Western audiences. The same consideration may need to be placed on the contents of the item mall, replacing "luck box" style items (where you might get a great prize or, more likely, a dud) with directly selling the better items.
Consider the difference between World of Warcraft's Celestial Mount ($25, 100% chance of getting what you paid for) with Atlantica Online's Enigma of Scheherazade ($1, some tiny (1%?) chance of getting a mount box, which in turn gives you a random chance of getting the mount you actually want). I'm not sure how many boxes people buy before they give up, but if it's less than 25, you'd be better off just selling the mount directly! Of course, if there's gambling addicts out there buying a LOT more than 25... well, I guess the financial success of the game speaks for itself, right?