There is only one broken thing in DnD, the one thing that leads to all the other brokeness, unbalancitude, munchkininnity, and powergamorical aspects of this game we play.
Players are broken.
They have too much power. They are allowed to thwart the carefully laid designs of the DM, often with no remorse, and certainly without punishment. They use the most seemingly innocuous spells creatively with no concern for how that might affect the DM's world, and give no thought to the fact that the DM has laid off using those spells against the PCs. They won't die when you want them cowed, only to die at the hands of the scrawniest minion in the BBEG's service. They are the only elements in a game world that do not bow to the slightest whim of the DM, and for this failure to conform should be excised.
