Answer:
It was their culture. They kept the body preserved. (in short)
Explanation:
Egyptians believed in second life, an afterlife, to be specific. A place they will wake up in with the things they have been mummified and buried within their tombs.
The three great Pyramids of Giza, for example, are tombs and they were built for pharaoh kings as something "great" that would best match their importance.
They mummified ancient Egyptians because their soul or spirit lived inside the mummified body. Egyptians thought this was the place where this soul or spirit could live. They thought there might be a chance that the spirit would go away if the body was not mummified or well preserved.
