Because that's the only one he knows.

I have a variety of EMs from Gottlieb, Bally, and Williams, and they all made some good machines. I am happy with my Flipper, Slick Chick, and Kings and Queens as I think these are some of the better machines Gottlieb made in that era.

As far as Bally is concerned, they were not big on flipper games until the 70s as most of their early machines were bingos. I do have a couple of gems though. Fireball is the game that really put them on the map, and it is a great multiplayer machine with several innovative features. Bally did not make many single players, but Bon Voyage may be their best. Great artwork and a near perfect layout with a variety of shots and a great spinner makes this one of the more popular games in my collection.

Williams made many great ones, but I prefer those from the 60s and prior. Big Daddy is my favorite with beautiful artwork and challenging gameplay that never gets old. I just picked up a Rocket, and it is not that hard, but very addictive to play. Trying to light up all the rockets on the backglass never seems to get old. Rocket is a surprisingly fast playing machine considering when it was made.