Why are Delirium's eyes of two colors?

Question

In The Sandman #21, some of the various members of the Endless families receive short biographic descriptions. Here's part of Delirium's (p 10):

For Delirium was once Delight. And although that was long ago now, even today her eyes are badly matched: one eye is a vivid emerald green, spattered with silver flecks that move; her other eye is vein blue.

Who knows what Delirium sees, through her mismatched eyes?

Is there a reason her eyes are two different colors? It appears from the above passage that it may have something to do with her development from Delight; is one color normally associated with delight, and the other with delirium?

The Wikia page says "One of her eyes is blue, and the other is green, though she can adjust them to the same color but says that hurts her," but doesn't mention why (in-universe or out) the eyes are different colors.

Answer 1

We can start by remembering the occasion when her eyes aren't of two colours:

_{Brief Lives, chapter 7.}

For a moment in Destiny's garden Delirium regains her sanity, reminding Destiny of the days when she was Delight.

_Ibid.

Though it's not evident from the illustrations (colouring errors are notorious when it comes to Delirium), Delirium's eyes are of the same colour when she's "collected".

Her eyes are of different colours to indicate that she is prone to split personalities - one moment she is kind, the other ruthless (e.g. when she gave the poor policeman the bugs).

Delirium's overall appearance is also changing, more so that her siblings'. Per Neil Gaiman, Delirium is the most changing of her family due to her age, and "Delirium" is not necessarily her final form.

NG: I decided Delight would would make for a very appropriate past existence for Delirium, because she's a character I wanted in a state of flux - she's been one thing, she's become something else, and eventually she'll change into something else again.

HB: Is this state of flux unique to Delirium?

NG: Yes. It has to do with her being the youngest; she's practically a cosmic afterthought.
_{The Sandman Companion, chapter 13 "Secret Origin", page 241 (first edition).}

She doesn't even care enough to remember which of her eyes the silver specks went to, if I'm remembering a page I can't find right now correctly.