I've owned the Defender and Stargate video games on and off since 1985.... would love to get the pin some day.
Quoted from Ronnie1114:It's a combination of the pinball industry as a whole not being very strong at that time and the complexity of Defender. I can only imagine how much it would cost to make that game.
Game difficulty was one of the initial criticisms of the video game as well, but that didn't stop the quarters from pouring in... too bad that didn't carry over to the pin.