Prior the World of Warcraft there was a number of popular MMOrpgs who had hundreds of thousand active players at a time. Games such as Ultima Online (1997), Everquest (1998), Dark Ages of Camelot (2001), Final Fantasy XI (2002), Star Wars Galaxies (2003), and EvE Online (2003). While these games were successful at the time, serving approximately 250-500k active players, their success was not remotely close to World of Warcraft's. In fact World of Warcraft has had more active subscriptions than all six MMOs combined.
So it’s easy to say that WoW set the standard, a standard that most investors and video game companies wanted part of. If you know a thing or two about the business world, businesses look to copy-cat other successful businesses. So it’s only natural for future MMO developers to not look at the mediocre games of the past, however; to look at WoW and copy it as close as they can but in the guise of a new name.
In truth, when a company finds a mark of success that is unheard of, it is normally hard for new-comers to copy the success. It has been more than ten years and WoW is still strong having more active players than all other MMOs combined (at least the subscription ones). Yet, many companies who tried to copy Blizzard's success have also failed. Though MMO industry isn't the only industry where businesses failed to copy the leading competitor's success. A prime example of a company (or industry) leading away from its competitors with tremendous success would be Disney.
Disney was the first animation studio company to reign in a huge amount of success on the big screen. Starting with Snow White in 1937 Disney’s first future film, earned approximately $66 million dollars (about $1 billion dollars in today’s terms) making it the highest gross selling animated movie of all time (adjusted for inflation). Even after Snow White Disney led the way in animation shorts and movies for decades, destroying it competitors for about 20-25 years.
Now I won’t say that Disney’s movie removed a lot of qualities in the animated feature films or even in animation itself because certainly Disney put in a lot of effort and quality in its cartoon films. However, the cartoon shorts were not the same anymore. What used to be violent, humorous, and funny were now innocent, sweet and funny. It took 20 years after Disney's success for Warner Brothers to come out with something totally different with its Merry Melodies and Looney Tunes to re-take the cartoon short industry from Disney.
In a way, the animation industry decided to forego something that was already popular, but less popular than Disney’s success on cartoons. The story is the same for MMOrpgs. Prior to WoW, MMOs were much different. Players had to form communities, play smart, and occasionally suffer setbacks. MMORPGs were a little bit less forgiving but allowed players to have their own adventure; it was set apart from today’s limited rails of questing and raiding.
But was this all of WoW’s fault? No, I can’t blame WoW for its success. However, at the same time I cannot say with a straight face that WoW’s success had nothing to do with the industry’s shift, because it clearly did. WoW made tons of money over the years and is still continuing to do so and its only natural for people to copy the success of others.
So like the cartoon industry, the MMO industry too has experienced the same glut of unsuccessful companies trying to copy Blizzard and its long standing MMO. In truth though, all industries go through this phase, but like with Warner Brothers and its Looney Tunes, it’s going to take game developers to develop something different from Blizzard's World of Warcraft to receive tremendous success.