The other correspondence between this oscillation between becoming and unbecoming, making a form and undoing a form is actually Heidegger's concept of Being, with capital B. His idea of sign is the world without a human view projected onto the world. It is the world as such, the world without human distinctions, without the grid of the categories that we project onto the world - I think this is what Heidegger means by sign.
Once you understand this idea, you will understand that we all have a desire - you know romantics called that 'the world untouched' - to see what the world would be without our view. What the world would be not philosophically objectively, but what it would be like to touch the world without this being our touch, what it would be to be touched by the world in an objective way. This is the Heideggerian dilemma because yes we do think that there is this Being, there is this sign, the world without the grid of human distinctions. But as soon as we, the humans, want to get it, we only have the world with our distinctions. Get my point?
We have this desire to get the world as a Nirvana, but without distinctions - even without soft lines-, but at the same time it is impossible for us because we cannot live without orientations, without our conceptions to have the world this way.
