You know a few people who claim to be witches. Did any of them actually ever cast a real spell; Like turning a prince into a frog?
I know a man who claims to have been a Navy SEAL. He was never a member of a UDT or SEAL team, nor did he attend BUDS. He is not, nor has he ever been, a SEAL. The mere fact that his mouth forms the words proclaiming him a SEAL does not make it so.
So, too, the "witches" and "warlocks" you may happen to know.