Back in the Correct Horse Battery Staple days and earlier, when password managers were still nonexistent or frowned upon, I used to recommend that if you had an executive that has trouble remembering passwords, they should use a phrase from a book in their office (make sure they have more than a couple of books in their office).

For all we know somewhere there's a wallet whose password is the first sentence from Moby Dick, or one of Hamlet's speeches.