Frequently compared to what?

No regime lasts forever, but by what metric would you assert that Egypt has been particularly prone to overthrowing its leadership? The Nasser/Sadat/Mubarak regime lasted 60 years, in spite of Sadat's assassination. The Mamluks lasted for almost 600 years, from ~1250 into the early 19th century, although much of this was under Ottoman vassalage. The Romans ruled Egypt for almost 700 years.