After your dog has demonstrated they can do the floor-level exercise of scattered sticks, you can move on to this elevated exercise. Walking over a line of platforms challenges your dog depending on how you position and space the platforms, the main thing is to have a bit of space between them but no so much space that your dog feels they have to jump.
Continuous motor skills like walking/running builds gross motor skills which help to improve core and limb strength, postural control, sensory processing, body awareness, balance, and coordination.
Be sure to have your dog on leash and moving in a safe controlled speed over the elevated platforms (i.e., not running or jumping). Do not use food to lure your dog as it will distract them from watching where they place their paws. If your dog displays any fear or anxiety, practice on platforms of a lower height to build confidence.