Yeah that’s very easy.All those mountains have been created for a purpose. To be seen. As grave or status symbol.
The bigger your building the more impressive it is. But without the modern things we have you like steel and concrete is to make a tall tower very difficult.
So the higher you come the harder it is.
Now in Egypt the Pyramids are not 1 2 3 as we know them.
This is one of the first pyramids and as you see it is not beautiful.
But in the end it only has to do with what is sturdy and what is not.
And a large triangle or mountain is now the best option.