Checking for characters

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(And a good indentation would make the code far more readable, Ctrl-I in Xcode editor will do it for you.)

let tenMostCommonPasswords = [
    "123456",
    "password",
    "12345678",
    "qwerty",
    "12345",
    "123456789",
    "letmein",
    "1234567",
    "football",
    "iloveyou"
]
let digits = "0123456789"
let punctuation = #"!@#$%^&*(),.<>;'`~[]{}\|/?_-+= "#
let password = "Pasword12!"
for _ in tenMostCommonPasswords {
    if tenMostCommonPasswords.contains(password) {
        print("Please change your password")
    }
    else {
        for _ in digits {
            if digits.contains(password) {
                for _ in punctuation {
                    if punctuation.contains(password) {
                        print("You're good to go!")
                    }
                    else {
                        print("Please add a punctuation")
                    }
                }
            }
            else {
                print("Please add a digit.")
            }
        }
    }
}

The expression digits.contains(password) gets true when digits("0123456789") contains the string password ("Pasword12!"). But as you see, "0123456789" does not contain "Pasword12!". So the else-close will be executed.

I guess you may want to do something like this:

if tenMostCommonPasswords.contains(password) {
    print("Please change your password")
}
else {
    for digitChar in digits {
        if password.contains(digitChar) {
            for punctuationChar in punctuation {
                if password.contains(punctuationChar) {
                    print("You're good to go!")
                }
                else {
                    print("Please add a punctuation")
                }
            }
        }
        else {
            print("Please add a digit.")
        }
    }
}

You may find this code needs to be fixed a little more, but it might be a good habit to leave a room for learning by yourself.