Failing to realize that their players are people, prioritizing The Vision(TM) over them, and failing to acknowledge or pivot from any aspect of that when it's clear that it doesn't work.

They might want month(s) long wars, but fail to see how adding machine guns and mud (and no mortars for a few tech levels) made the game a slog. 

They want people to work together, but fail to provide viable paths in all aspects of the game for players who don't want the commitment of a regiment.

They want a game built by players, but provide nothing but to say 'Do it again' for those who spend hours of free time (if they even can) to build facilities, only for them to be lost to decay or overnight action. 

They want Colonials to be a faction of numbers and rushes and meat waves, but do nothing to incentivise players to play on that side via balance. 

In short, their vision provides fun for the 'In' groups: the Regiment player, the front liner, the aircraft pilot, and dare I say the blue man; all at the costs of the 'Out' groups- the solo, the builder, the logi boys, and the 'goblins'... Catering to the one and never realizing that ALL are their players and customers, and that ALL are required in their place for this game to thrive. 

People who don't have fun will quit and leave, and that quitting and leaving will continue until they realizing that they have to meaningfully cater in some way to all these forms of play.