The Colossus of the Profane Goddess

 When I first played The Legend of Zelda - Ocarina of Time (1998) as a child I had no idea what a "colossus" was supposed to be. Wasn't all that clear on "desert" either since I had to learn English specifically to understand the game. Poor utilization of the dictionary meant that for a while I thought it was simply supposed to be a big desert (as in colossal desert). Of course the name of the area is referring to the giant female statue carved in a massive stone monolith which forms the front face of the Spirit Temple, withering away with age, and the final destination of Link's journey before he faces Ganondorf.

The Colossus of the Profane Goddess
The Legend of Zelda: Ocarina of Time

The society of desert-dwelling all-female thieves (with the exception of the single male born every hundred years, our antagonist Ganondorf) have a giant likeness of themselves—seemingly in meditation—on their sacred site. In the Japanese version of the game this area is named "巨大邪神像" (kyodai jashinzou), and reveals that a fair bit of subtext was removed in translating it as "Desert Colossus". Instead a more accurate translation would be something along the lines of "Colossus of the Profane Goddess" (literally "Giant Evil God Statue"). It is no longer a mere colossus, but explicitly a giant statue dedicated to an evil goddess. Presumably this is not what the Gerudo themselves call their most sacred site, and it is doubtful Link would be so judgemental (within the context of the game, who names these places?).
The Gerudo are the most vilified race in the game that aren't explicitly enemy creatures (not in the least because main villain Ganondorf is one of them), and initially hostile to outside intruders. However when you actually explore their territory it turns out they're basically just a different culture trying to survive in an inhospitable environment—in Wind Waker Ganondorf explicitly rationalizes his turn to villainy as him initially wanting a better life for his people—and their temple inside the "EVIL Goddess Statue" is the closest we get to a temple that resembles an actual a place of worship. It is occupied by Ganondorf's twin mothers, and corrupted by his attempts to choke Hyrule into submission like the other temples, but still.

Then we get to Kakariko Village, a nice pleasant village housing parts of the culture that probably helped vilify the Gerudo and labelled their goddess as "evil". Kakariko Village is the main settlement occupied by humans and Hylians after Castle Town is destroyed so it is probably safe to say it houses the dominant culture of Hyrule for the majority of the game. That nice village is home to not one but TWO dungeons that are literal torture chambers with entire rooms made of skeletons hiding Hyrule's bloody history. That pleasant village we have been traversing multiple times turns out to have hidden the evidence of mass genocide beneath our feet. And these are the people referring to a different culture as "evil". Both of these dungeons also have the theme of "seeing the truth". A not so subtle reference to how the peace in Hyrule was bought with lots of blood that has since been swept under the rug (the well connects to one of these torture chambers. Just what is in Kakariko Village's drinking water?).

The top deities (the Golden Goddesses) of the celestial matriarchy of Hyrule are Din (representing power), Farore (courage) and Nayru (wisdom) who are depicted in the game as shaping the world of Hyrule and leaving behind the Triforce on the spot where they departed back to the heavens. It seems unlikely that the goddess of the sand depicted in the colossus is supposed to be a fourth Golden Goddess who for some reason was cast out, but it might explain why the Gerudo can hardly be said to benefit from the creation of the Goddesses. Unlike the other races they have to survive in an inhospitable desert. Hyrule has plenty of protector deities that do not profane the Golden Goddesses with their existence (Lord Jabu Jabu, the Great Deku Tree, pre-corruption Volvagia), so why does the protector deity of the Gerudo?
Contradictory to this is how the Spirit Temple does house a sage that fits in with the other seven, and the Triforce is depicted over the entrance. The colossus itself is also so old that its façade is visibly crumbling. With what we know from the other games in the series, perhaps this indicates that the religions of Hyrule are in no way static, and at one point in the past the currently absent goddess of sand was part of the Hylian pantheon until she fell out of favour.
A further interesting detail is the presence of a Great Fairy Fountain very close to the colossus. The reward for finding it and summoning the fairy is the protection spell called Nayru's Love. Nayru, as previously indicated, is the goddess of wisdom but she is also associated with water. The other two goddesses represent fire and wind—which in a desert environment would be extremely undesirable elements—but water would bring life. The colossus of the goddess of sand may in reality be an attempt by previous generations of Gerudo women to petition Nayru specifically to ease their living conditions, and it was misinterpreted by the other races of Hyrule as depicting a separate goddess entirely. It would certainly explain why the protector deity of the Gerudo is missing from the game if the depicted deity went back to the heavens with the other two.

A solid explanation of what the colossus represents is hard to determine. However the world of Ocarina of Time is interesting precisely because so many locations raise a lot of questions that the dialog only ever hints at but never explains. Why is the Forest Temple a mansion haunted by four female ghosts? What exactly happened in the past for the Shadow Temple to become a torture chamber? It presents Hyrule as a proto-Dark Souls world where understanding goes against the point, and the world becomes richer for it.

Sources

• The Legend of Zelda - Ocarina of Time (game, 1998)