@markwyner I can agree that they aren't moving but cannot agree that they aren't changing, and moreso than just a little - if you focus on just one line of one cube you can see that the shadow/outline part that lags just behind the rest of the black/white flash effect will change which side of the line it applies to each time the arrow changes. this is what causes the change in cube motion effect. it is not just the arrow icon that changes.

the original illusion claims that the lines of each cube do not move and that is the only correct assertion about this illusion - other false assertions (that e.g. the effects also don't change in any way) were brought upon only by telephone game.