Of course this is incorrect, go look up an empire and see.
... Roman empire got over 1000 years, Ottoman's got 623 years, Mongol empire only got 162.
...and Italy, Turkey, and Mongolia are still around, they're just not empires anymore. They're Nations.
these where the first versions of empire that existed on this world and full of equal parts flaws and dumb luck as a result
the modern hybrid euro-colonial versions also have flaws and luck on their side, but, more importantly, they learn and adapt from each other and, as a result, have a pattern that we can now identify.