The sun bathes us in natural light, even when covered by cloud. But for part of each day it is hidden from our sight, lighting the other side of the world. Our ancient ancestors learned to make fires, to keep the threats that darkness held at bay (as well, of course, to keep themselves warm). Since then mankind has developed all sorts of artificial ways to mimic the light of the sun when it disappears at night.
The most successful buildings are those in which form and function work in harmony. Buildings that not only look amazing but serve their purpose well. And also, buildings which reflect the culture of their location and contribute to it, rather than tug against it. The Louvre Abu Dhabi is one such building.