In Python, Whenever I try to compare a string input to a variable that is a string, it will not work

I am new to Python and am currently trying to make Rock, Paper, Scissors to learn the language better. I, however, am having issues when asking the user for a choice. Here is the function that is acting up.

    global userAnswerINTEGER
    global userAnswer
    global rock
    global paper
    global scissors
    userAnswer = input("Rock, Paper, or Scissors? ")
    print(userAnswer)
    userAnswer = 0
    if userAnswer == (rock):
         userAnswerINTEGER = 1
         results()
    if userAnswer == (paper):
        userAnswerINTEGER = 2
        results()
    if userAnswer == (scissors):
        userAnswerINTEGER = 3
        results()
    if userAnswer != rock or paper or scissors:
        print('Please, pick a valid answer choice.')
        askUser()```

I have additional variables within the file.

rock = "Rock"
paper = "Paper"
scissors = "Scissors"
userAnswer = 0

However, no matter what I put in the prompt, it will always print 'Please, pick a valid answer choice.' How do I fix this?