@Janichsan With pool balls that big, I‘d watch out for the cue! With the angle, one seems smaller than the other 2. I’m sure there’s a story behind the placement.
The story is in the title: this sculpture is really called "Giant Pool Balls" and is supposed to be just that. The ball in the background is the cue ball and when played at the right angle, the middle ball pushes the left one into the "pocket", which is a semi-circular platform in a lake behind the vantage point.