Although Revenge from Mars was a sucess approx 7,000 machines sold a success in anyones books. Star Wars however did 5,000, that is still a success and there where a few contributing factors to why

Star wars did not get released and the same time as the movie and interest was not as high.

The increased price saw operators pull out.

In comparison Sega released South Park and sold only half of Williams Star Wars approx 2,200. So the question was Pinball was making a profit but how much of a profit was enough?