You can set certain posts in several positions that can help a player (liberal) obvious example being the side/outlanes being closed off a little tighter. Upper roll overs are a very slight bit easier if the configuration is changed to allow the ball to go into the middle lanes on some games as well. There are other examples, but you get the idea.

I would say that Gottlieb always set the games to conservative at the factory. Most games I have worked on, have the posts set that way, with the more liberal positions having just the factory dimple, but not having been used.