Nostradamus and those 'prophets' like him were more wrong than right in their predictions,
any man with blind guessing would guess that much, even more with some reasoning.
One clear and recent example, I remember, is the solar eclipse in 1999., the story was like
999 is 666 reversed, and the devil and total darkness is coming yadda yadda yadda.
I don't recall something like that happened.
Nostradamus and any of those found an effective way to manipulate their people, by
calling to 'mysterious' powers, what makes them seem credible is than they lived long
ago, and their existence is veiled in mystery, so they look like they knew what would happen.