We really can't say much about the building of the pyramids. That's mostly because the Egyptians - if indeed they built them - had almost nothing to say about it themselves. That may be the oddest thing indeed among a host of odd things we encounter when trying to make sense of the construction of the pyramids, particularly the most sophisticated ones such as the Giza pyramids.
While it is true that the Egyptians were not the meticulous historians that the Greeks and Romans later became, they nevertheless kept fair to middling chronicles of much of their lives including their battles, their genealogies, and their sciences. Why they would have almost entirely skipped over the erection of some of the most remarkable edifices in history remains a mystery. Scientists and non-scientists alike have tried to fill in these gaps over the passing centuries.
So-called Egyptologists usually have their views validated most often. But they are almost like a club, helping to serve the national pride and the tourism needs of modern Egypt. They know which way their bread is buttered and are unlikely to challenge the status quo. Whenever doubts are raised about the lack of tools and expertise needed to build these enormous structures, we are assured the Egyptians simply found a way to do it whether we can fully explain all the details or not. Textbooks are still likely to show the old absurd pictures of whipped slaves supposedly pulling the humongous rocks along with super-strong ropes that didn't really exist. But that view has lost favor even with the Egyptologists who are now pushing an agenda that suggests it was an all-volunteer effort and that the construction was actually an exercise in civic pride; something akin to our Olympic Games where teams competed against one another for presumably rock hauling honors. Indeed, it is a more politically correct story for the tourist brochures
It's not a perfect story and it may not even be a true story, but it benefits from the weaknesses in much of the competition. We have the UFO people, the Atlantis people, the Levitating Angel people and a host of others ready and eager to associate the pyramids with their various pseudo science beliefs. But it's the same problem: no real evidence either for the "science" or for a connection to the pyramids.
What was the point in building these monstrosities? We are most often told they were constructed as tombs for the pharaohs. Indeed, no matter who built them, it is true some dead pharaohs were put inside some pyramids. But in the case of (among others) the Great Pyramid the granddaddy of all pyramids - no body has ever been found. The only "evidence" suggesting it was built for burying the powerful ruler Khufu consists of a small piece of graffiti in some remote part of the structure. And of course we know many pharaohs and other Egyptian nobles were not buried in pyramids at all, but rather in underground tombs such as the Valley of the Kings.
Whatever the truth may be, we encounter similar problems in coming to grips with other structures of massive size and complexity - Stonehenge, the pyramids and temples in the Americas, among others - that seem to have exceeded the capabilities of the relatively primitive societies that may have built them. It's interesting and intriguing. We can't say much more than that.