A comment I found on greatest cinema villains,
Voldemort and Darth Sidious/Emperor Palpatine:
“Voldemort's problem was that "Spam Crucio and Avada Kedavra" was his answer to everything. Voldemort's "I'm evil and will torture you into insanity then kill you" was unsubtle and was never going to work.
Palpatine put on a nice guy act and pretended he was working for the galaxy's good while secretly organising an invasion of his own planet to force Valorum to step down after being unable to stop it so he could become Chancellor.
Used Dooku and other people's problems with the corrupt Republic to form the Separatists to create a fake threat to justify creating the clones he actually intended to use to kill the Jedi.
Tricked d*mbass Jar Jar into giving him emergency powers.
Framed the Jedi for trying to overthrow the Republic and used the emergency powers and Mace Windu's attempt to kill him to get sympathy and form the Empire.
Only showed his true evil self when he had all the power and didn't have to hide it anymore.”
“To be fair, spamming those curses worked right up until some kid had plot armor.”