The reason why? people get mad @ Warmane. Its due that they put out an expansion and then they leave it behind broken to release another expansion.
If you track the sequence it goes like so: LK>CATA>MOP>LK. The reason he aims the hate on Cataclysm is due that it has been out for so long and nothing gets fixed (small fixes due to people QQ). Many classes have broken specs, and some are 90% broken to the point that, they have become useless due to " lets break it and not fix it since we can't" A good example way back was Warlocks, and now its Fire mages.
If they took the time to fix and work an expansion before releasing a new one and reducing the quality of the ones already out. Then I might disagree with Dodgykebaab. The worst mistake Molten/Warmane has ever done was releasing Mop, then followed by Lordaeron. Keep in mind they were trying to get WOD out after Mop, wich it would have been even worst.
You don't skip things b/c you can't fix them. You fix them and then you move on. I think my oldest account is from the end of 2009 to start of 2010. I have notice when new things come out, more things become broken, but then again you can't expect everything to be working when they are trying to please many people. Who have differents liking in different expansions.