Why does this machine walk like a penguin?

Why does this machine walk like a penguin? Meet this Russian dragline excavator from 1979 resembling a crane. Weighing 600,000 pounds, its massive size caused sinking on tracks, leading to unique penguin-like pads. These help it inch forward, addressing its slow movement due to extreme weight. Note: "The appearance of U.S. Department of Defense (DoD) visual information does not imply or constitute DoD endorsement."