With how many people that work on big-name games, and are also shown in the credits, I'm baffled how they can't do certain jobs up to par and end up with glitches by the deadline. That really brings less immersion. But if some company wants to try something new, there is no incentive because most gamers like more of the same as long as it relates to their collection. Or at least that's what they deliver that they think we want.
It is unfortunate that some gaming companies show a very nice looking game trailer, but the game release date delayed, or the game have problems like glitches which make it unplayable.