Well, here I go, others can adjust when needed.
Since Return of the King, Decipher found out that they were paying a lot for the licence that made it possible for them to even produce the cards. They needed to make more money, so they took a few measures to do so:
- Increasing the strenght of the cards, degenerating earlier cards
- Making new mechanics that led to overpowered combo's
- Introducing Decipher dollars, when playing a tournament you could only win Decipher dollars, which was, especially for the tournament players not very interesting. A lot of players quit and started, or returned to either WoW, Magic and a lot of players started playing poker, Texas Hold'em.
- No testplaying. There was at the end only 1 designer, that didn't do a lot of testplaying, which was sad. There were soooooo many players, that were dedicated to the game in all so many ways, that offered to testplay free of charge, in order to help the game, but all were neglected.
Again, feel free to add, where I am missing things, or where I am off