Ya, except that that was almost a decade ago. When WoW was released, people could see that it was different and had huge potential. If companies keep trying to release unpolished wow clones the customers will keep going back to wow. People want to leave wow. It has gotten stale despite all the updates and everything. Just think about that. WoW has 7-8 years of content and people are bored. How can anything unpolished compete with that?

Look at swtor. It has a completely polished leveling experience. For one character. If you roll an alt, there is no "I've already done this zone, I wanna level in another with different quests." It's the same quests, in the same order, except for class quests but those alone will not get you to level cap. And when you get there, what is there to do? A couple easy FP's and broken PvP. Know what WoW has? An entire expansion worth of content and 3 other games worth of stuff to roam around in.

If a company wants to get a pay mmo going for more than a year, they need to do something drastic and do it well.