they know the problems, but fixing them... if you know ANYTHING about coding you'll know sometimes things get very complicated very very fast, and when let's say, most of the people are focusing on polishing off TBC content for Lordaeron, 2-3 people won't have a lot of success fixing a load of very broken mechanics in any sort of time you as a consumer would find appropriate... it's just a matter of time...
and if people keep doing that thing you can see if you scroll up about people saying it's going to be 'too late' and just patiently sit in their expansions, sure making characters elsewhere for a different experience, but not give up on it...