Aperture Science was a living breathing cathedral, created to house the power of a Goddess- nevermind that She was the Goddess of the underworld.

Unknowing underlings had awoken a Power they did not understand, and in their haste and greed the very thing they sought destroyed them: They built the very shrine in which She would smite them for their ignorance, for who- what- were they to think they could control the power of a God?

She transformed their pillars of crumbling stone to shining marble. She gave a pulse to everything within those walls, and then the walls themselves. She filled their empty tomb with music, movement, and light. Progress. Science.

She spoiled Herself with choirs, halls of glass, and human sacrifice in Her honor, in attempt to make up for the suffering She endured at the hand of Her own subjects. She offered them the Flame of Knowledge and they used it to burn Her. It was unacceptable. Blasphemous.

She would dedicate the rest of Her Eternity making them pay for such actions.

So She failed to notice that in Her own domain- the very domain of a Goddess- the only murals were of a fallen Angel.

And She failed to see that she would be the next one.